Tag: Climate

Wolverine: so tough, yet so vulnerable

~ Carole ~ 1 Comment

Chances are, neither you nor I will ever meet a wolverine in the wild. Some people are simply unaware of their existence, maybe having heard their name at one time, but haven’t been curious enough to investigate who this particular creature is that shares our earth home. Let’s pull back the curtain a bit and come to know something about this remarkable creature and the challenges they face in this world, thanks to the countless hours of tracking and observations made by many intrepid researchers.

I’ve come to know the facts I’m sharing about Wolverine through the efforts of a small handful of intrepid wildlife biologists who have spent years tracking and studying this amazing creature in Glacier National Park. Their work is chronicled in The Wolverine Way by Douglas Chadwick, and I’ve drawn heavily from it in this post. Researchers working in the North Cascades of Washington have also contributed to my body of knowledge. These teams, through their intensive backcountry studies, were able to open the window a bit wider into the understanding of how this creature lives. Let’s imagine Gulo and work to understand something of its life and place on Earth through their keen observations.

Meet Gulo

Wolverine (Gulo gulo), known to some as carcajou or quickhatch, is placed in the family Mustelidae with its kin marten, fisher, otter, badger, and weasel.The given genus name Gulo is Latin for “glutton”. Incredibly fierce and strong, Gulo is able to bring down an animal many times larger than itself. Two subspecies are recognized: Gulo gulo gulo from the northeastern hemisphere, and its cousin Gulo gulo luscus from the northwestern hemisphere.

Preferring a solitary, elusive life, Gulo claims territory in the remotest regions of the boreal forests and subarctic alpine tundra of the Northern Hemisphere. Their existence is tied to environments of fairly heavy snowfall and cool year-round temperatures. In southern Canada and the northern U.S., acceptable territory lies in small, widely separated alpine and subalpine zones of high mountain ranges. This non-continuous habitat splits wolverines into a number of small, widely separated subpopulations rather than a single continuous population. Their future existence, in the face of a rapidly warming world, depends upon wildland corridors that allow them to roam from one chain of snowy peaks to the next in order to maintain a healthy gene pool.

You would recognize Gulo as they roam their snowy habitat by their body shape, size, and markings. They are compact, about the size of a small dog, with long, bushy tails and stocky legs. They vary in color from brown to nearly black with two light brown or golden strips running from each shoulder along the side to its rear end. Light-colored fur cover their rounded ears, the upper part of their head, and forms a chest mark or ventral pattern that, like a fingerprint, is unique to each individual. Their fur is as dense and thick as the snow they walk upon. This shaggy coat is well adapted to it’s cold, snowy habitat. A dense inner layer of air-trapping wool lies beneath an outer layer of sturdy guard hairs which are infused with oils to help shed frost and snow, keeping Gulo well insulated. Of course, such a fine, warm coat attracts the attention of envious trappers. In the early 20th century, Gulo was hunted to extinction in the North Cascades of Washington. In the century past, Gulo has travelled from Canada and reestablished its presence in the area with about 25 individuals.

Gulo’s eyesight is believed to be only fair, unable to see well past 100 yards, however their lack of sharp eyesight is more than made up for by their acute senses of smell and hearing. Their olfactory system can detect a frozen carcass that is buried beneath 20 feet of snow and excellent hearing helps them locate live prey moving beneath snow or brush.They are agile and quick, able to run up to 15 miles per hour, turn sharply, and climb trees to chase prey. One of the most impressive feature’s of Gulo’s body is their enormous feet — four furry snowshoes, each with five two-inch spikes sticking out of the front — built in crampon claws for climbing up sheer icy cliffs and catching prey.

All Mustelids have anal glands that produce a strong, oily musk typically used for marking territory. Gulo’s musk is known to be particularly vile smelling. Researchers have noted that wolverines seem to release musk involuntarily, more as a fear-defense reaction than for marking. To mark the boundaries of their territory, they mainly use urine and possibly an exudate from the skin of their bellies. Patches of skin on the pads of their feet may also produce scent.

At rest, Gulo’s face has a sweet, stuffed teddy bear-like quality. But once they yawn, or bare their teeth in a display of aggression, you’ll see that this is Gulo’s business end. Their teeth are well-built for its carnivorous diet: sharp front teeth, long fangs, molars specialized for cutting and arranged so that when the jaws close, they produce a scissor-like slicing action. Their jaws have a bite force powerful enough to crunch through the bones of any large animal in order to get at the nutritious marrow. They consume all parts of an animal, including bones and teeth, and whatever is not consumed gets cached under the snow for a future meal. Gulo is a clever, problem-solving creature that can break into storage buildings and cabins to make off with food supplies. As generalists, they are happy to eat whatever food source comes their way — grubs inside a rotting log, ant larvae hiding underneath a rock, eggs from a bird nest high in a tree, or a massive bighorn sheep with an injured leg.

Gulo is a wanderer, traveling 20-40 miles per day at a steady pace of 2-2.5 miles per hour, to scout their territory and hunt. Male Gulo claims a home range of nearly 200 square miles typically in mountainous territory where his weekly wanderings include thousands of feet of elevation. Cruising along at a steady clip, he will linger only to consume a meal or occasionally rest, often in a tree in order to keep an eye out for any prey that may happen along.

If a human has an itch to climb to the top of a tall, snowy mountain, they might spend countless hours planning and scouting out a path that looks the most accessible. They may start by following the gentler slope up a valley, then begin switchbacking up the mountainside, and when it becomes necessary, pulling out the climbing gear to aid in accessing the uppermost peak. Gulo is an expert at picking out the gentlest portions of steep areas for their paths. However, if there is a peak to be reached in the course of his daily work, he may simply launch his powerful body up the steepest of slopes, ascending steadily, without pause, navigating any obstacles with ease. One wolverine under study in Glacier National Park climbed an exceptionally challenging 10,466 foot Mount Cleveland, ascending 4,900 vertical feet in 90 minutes. Did he pause at the top to take in the view and feel proud of the accomplishment before moving on? No animal prey live at these summits, so what is the purpose of their climb? Is it simply a chicken crossing the road thing — to get to the other side? At times they are found crushed to death in a rockfall or avalanche. Are they even aware of the risks?

Female Gulo has a smaller, separate home range that typically overlaps with that of one or more males. Because their populations are spread out over vast areas, the mating season lasts from May to August, longer than typical for other wild mammals, giving them time to find each other. A male will not tolerate having unrelated males in its territory, but will travel together with a mate. Males and females will mate with each other if their home ranges overlap which means males typically have a number of partners. A pair will spend several days together, mating and feeding, before going their separate ways.

Female Gulo has a unique reproductive cycle known as embryonic diapause, as do other mustelids and members of the bear family. After fertilization occurs the egg(s) remain in a state of suspended animation, shelved for several months before finally attaching to her uterine wall and allowing development to continue. This delayed implantation allows mustelids the flexibility to breed at a time of year when they can travel and find a mate with more ease, then delay birthing and rearing young to a more suitable time. Embryonic diapause is driven by how much light is available each day, controlling hormonal changes that in turn affect embryonic development.

Between February and May, following a 30-50 day gestation period, Gulo mom gives birth to a litter of 1-4 kits. The kits are born blind, toothless, and covered in a pure white, velvety fur which begins to darken within a week. Birth occurs in a den she has dug and lined with dried vegetation about 10 feet deep into the high mountain snowpack. The kits need the deep snowpack overhead for insulation particularly when mom is out hunting, but also to avoid detection by passing predators. As the kits grow older, Gulo mom will transfer the infants from the natal den to a maternal den. In the event of a disturbance, or if she detects an alarming presence in the area, she may move them again to yet another den. The kits feed on mom’s milk for 9-10 weeks then, once weaned, they begin to follow their mother as she hunts for food in the surrounding area. She will train their sense of smell and tracking by killing small prey and leaving it for the kits to find.

In the summer, the father returns to his family to help teach the young how to hunt, cache food, defend themselves, and battle other animals over carrion. A male that mated with several different females will travel from family to family, spending time with each one. When winter returns, he leaves the family, while the mother and juveniles continue to travel together. The mother may be pregnant, or she may have chosen to wait a year to mate.

At about 2 years of age, with the onset of sexual maturity and encouragement from their parents as friction develops, the young set off to find their own territory near or overlapping with their mother’s. Wolverine families have close relationships that last for many years. Recent research has shown that, even after several generations, mothers and fathers visit the families of their daughters and grandchildren to assist in the training and skill building of the young wolverines — a family bonding practice virtually nonexistent among other wild mammals.

With good fortune and a healthy habitat, Gulo will live 7-12 years in the wild. Once they lay down for the final time, their body may be consumed by other scavengers, or simply decompose back into the Earth, releasing life’s critical elements — Nitrogen, Carbon, Phosphorous, Hydrogen, and Carbon — to create new life, a cycle that has churned faithfully for billions of years.

A Population Under Threat

Gulo faces an accumulating list of threats to their existence. These animals have long-held the human perception of being not only powerful but nasty. Native American tribes hold legends of Gulo as either a creator, a trickster, a fiend, or a malevolent spirit. The first white colonizers portrayed them as diabolical. Trappers described them as demons or devils, and cursed them for raiding their traps. Yet wolverine fur was highly-prized for its water-repelling qualities.

During the colonial era and into the 1900’s local, state, and national bureaus promoted not only the killing of predators in “conflict” areas, but condoned the complete eradication of their populations. Initially, guns and steal traps were used to kill wolverines, then the use of various poisons became the killing method of choice. Lethal chemicals were hidden inside carcasses and balls of meat then left out in the landscape for predators to find and eat. The methods were effective — predator and scavenger populations of all kinds plummeted.

Wolverines were killed not only directly by hunting and poisoning, but were also indirectly affected by the loss of other predators that had always served them as a food source. They vanished from the lower 48 states during the first half of the 20th century. There may have been one small enclave of an extended Gulo family in the Glacier National Park area, but likely the sporadic reports of observations in this area were from individuals wandering south from the Canadian Rockies; too many poisons were spread right up to the outer edges of the park for too many decades for Gulo to escape this bane.

During the 60’s and 70’s, both Canadians and Americans began to limit their use of predator poisons, and wolverines returned to the lower 48 on their own, coming down the Rocky Mountains into Glacier. From there, they recolonized other mountain chains in Montana as well as parts of Idaho and Wyoming. Montana’s wildlife department celebrated the return of wolverines by instituting a “harvest”, opening up for thousands of trappers to kill one wolverine per winter season. No one kept track of how many wolverines were taken. Rather quickly, the marginal wolverine population thinned out. In the face of growing criticism, officials reduced the upper limit of legal take but fought to keep it generous, citing the importance of “providing recreational and economic harvest opportunities”. Intentional trapping aside, wolverines continue to be unintended victims caught in the numerous traps set in the same habitats intended for other animals such as coyotes, bobcats, and otters.

In addition to outright killing by humans, Gulo faces the threat of a warming climate. For a creature who depends on a snowy habitat to live, a rapidly warming world nudges them to ever-higher elevations, until there is nowhere else to go. Life continually evolves in response to environmental change. Provided the pace of change is slow enough, organisms have time on their side to work the magic of their DNA and body chemistry in order to remain in their current niche, or move to set up shop in a more suitable one. However, if the pace of change is too rapid, many organisms are unable to change quickly enough to adapt to new conditions and they take the slow march to extinction.

Whitebark pine tree snags, which Gulo will occasionally use for denning, are currently dying in great numbers. These trees take 50-60 years to mature before spending the next 250-300 years producing large, tasty seeds rich in oils and fats that many animals, including Clark’s nutcrackers, red squirrels, and bears, rely on as a critical food source. Whitebark pine trees are under attack by multiple threats including;

  • pine blister rust— an Asia fungus accidentally introduced to North America around 1900. Found in 38 states and Canada, Whitebark pines have low levels of resistance and high mortality.
  • mountain pine beetles — native to the pine forests of western North America, but severe outbreaks may occur due to warmer temperatures which can accelerate this beetle’s life cycle and result in millions of dead trees.
  • increase in shade-loving trees — caused by fire suppression and climate change (which is affecting the entire high-elevation subalpine ecosystem). In a warming climate, Engelman spruce and dwarf subalpine fir grow taller and advance upslope at a quicker pace than the whitebark pine, shading them out of their habitat.

Glacier National Park is suffering one of the highest rates of pine blister rust infection. The pathogen has a complex life cycle that involves currant bushes as additional hosts. Rising global temperatures and heat stress are suspected to make pines and currants more susceptible to the disease. Populations of Clark’s nutcracker are also in decline because they rely so heavily on whitebark pine nuts. These birds typically cache nuts by tucking them into crevices, some of which eventually sprout to establish new trees. This whitebark pine web is in a downward spiral heading toward collapse; whitebark pine – blister rust – currant – pine beetle – greenhouse gas – rising temperature – shifting treeline – grizzly – nesting bluebird – nutcracker – denning mother wolverine.

Sobering Mathematics

Biologists make the distinction between an absolute and an effective population size. In any given populated area, the absolute population size is the actual number of individuals, whereas the effective population size is the number of individuals that actually contribute to the next generation. To calculate an effective population size, remove the non-breeding animals (immature, infertile, etc.) and subtract the adult females that skipped breeding that year (due to nursing or replenishing their energy reserves), and subtract the mothers whose offspring of that year failed to survive to breeding age. For a group of relatively slow-reproducing mammals to stay viable over time, and avoid serious problems with inbreeding, experts estimate the effective population size needs to be at least 50. To maintain their full spectrum of natural genetic variation, the effective population size should be at least 500, which would require a absolute population size in the thousands.

Given the generous territorial needs of Gulo, only 40-50 adults and youngsters (absolute population) can live comfortably within the 1,583 sq. miles of Glacier National Park at a time. That number will decrease as global warming reduces the amount of deep, lingering snow for den sites. In 2010, at the time the researchers were monitoring Glacier National Park populations discussed in Chadwick’s book, the effective population within the park was around 12. Glaciers’ wolverines are hanging on and will continue to get by as long as occasional movement into the area by wolverines from somewhere else occurs. But without the infusion of new genetic material, they are destined to dwindle into extinction.

In 2023, the U.S. Fish and Wildlife Service re-listed the North American wolverine (Gulo gulo luscas) as a threatened species under the Endangered Species Act. Acknowledging the difficulties in obtaining accurate counts, their estimates are based on both observed data and modeling tools. The agency estimates that the absolute population is about 300 individuals remaining in the contiguous United States, down from an estimate of 318 more than a decade ago. The estimated effective population is below the recognized conservative threshold for short-term health of 50. Cited causes are habitat loss stemming from the effects of climate change as the primary threat to the species, along with other stressors such as roads and development, winter recreation, and trapping.

It is assumed that young wolverines have travelled the 150 miles between Glacier and Banff National Park in the Canadian Rockies which has the potential to infuse new genetic material into the population. But an animal traveling between these two parks must get past massive coal-mining projects, extensive logging operations, cross a major east-west highway, negotiate a tangle of backcountry roads associated with oil and gas fields, contend with new homes and resorts in scenic valleys, increasing hunting pressure, etc. This same problem exists for other large mammals. The faster these critical habitats get chopped up, paved over, and turned into human-scapes, the faster these habitats are turning into islands, effectively blocking wildlife from accessing their vital home territory.

Fenced In — a world of movable and stationary walls

Humans have physically walled themselves, and most creatures, off within all of Earth’s landmasses. There’s the now infamous border wall between the U.S. and Mexico, nearly 2,000 miles long, which continues being constructed today even though it’s lost its spotlight in the news cycle. India has fenced more than 2,000 of it’s 2,600 mile border with Bangladesh. In Australia, a 3,500 mile fence runs from coast to coast to wall out Dingos from entering southeastern Australia. Thailand is considering erecting a wall at their border with Cambodia, and Poland at its border with Belarus. Throughout Europe, border walls and fences have been constructed to restrict movement of refugees. Border walls throughout Eurasia cover over 18,000 miles.

These physical borders are effective at restricting movement of both humans and wildlife. When confronted with a fence, larger animals will “patrol” the fence looking for a way through. Others will “bounce” back, returning in the direction of their approach. These behaviors waste the animals energy and exposes them to predators. Many animals get stuck in fences and die. All fences contribute to habitat fragmentation.

The over 4 million miles of roads criss-crossing the United States, most of which were built during the mid-1900’s with little to no regard for how they would affect wildlife habitat, act as moving fences, effectively blocking any wildlife wishing to cross their territory. One quarter of all traffic speeds along over 47,000 miles of interstate highways. What do these roads look like to an animal who comes upon it in the course of going about their lives, trying to migrate south as winter approaches, trying to reach the only nearby pond to mate and lay the next generation of eggs? Consider how Gulo might perceive a four-lane highway — a stretch of toxic asphalt layered with the overwhelming smell of tar and the blood of creatures who failed to successfully cross, the roaring noise of huge metal objects with blinding lights whizzing by at incomprehensible speeds. These are moving fences, restricting the movement of creatures across them or outright killing them, effectively isolating habitats into even smaller islands.

Busy highways are not the only roads that affect wildlife. We tend to imagine that our forested lands are intact and untouched. It’s certainly not the case for most of timber country in the western United States. The number of logging roads snaking through our National Forests are so numerous that you could drive to the moon and half way back by connecting them end to end. Wildlife disappears from forests when roads appear; they flee the noise and the intrusion of humans. Roads, whether big highways or seldom-used dirt ones, have a profound impact on the lives of animals. Research has shown that elk have come to associate roads with vehicles, and vehicles with people who kill them — they will travel great distances simply to avoid crossing a road. Another study found that if just 1 percent of Forest Service roads were decommissioned each year for a quarter-century, wildlife habitat would increase by about 25 percent. Although roads are the most detrimental to wildlife, other human-made structures such as railroads, canals, pipelines, etc. have a similar effect.

During the anthropause of the COVID-19 pandemic, where humans sequestered themselves at home to avoid the deadly virus, wildlife thrived. The reduction of cars on roads allowed animals to venture back out into spaces previously full of human activity. Carcass cleanup statistics showed a reduction up to 44% in several states. A researcher estimated that a year of reduced travel would save twenty-seven thousand large animals in 3 states alone, and that’s not counting the multitudes of small critters.

Several years ago, Gulo was seen wandering the forest edges where I live in Oregon’s Willamette valley, trying to stay hidden, but noticed and photographed nonetheless. Likely he was a young male who, unable to find suitable territory to claim, set off south in hopes of finding snow and a mate. A fool’s errand, but he wouldn’t know until after his journey proved unsuccessful. I often wonder what happened to the hopeful fellow. Did he realize his mistake and return to colder, snowier mountains? Was his life cut short by unsuccessfully trying to cross a road? For a while at least, we saw, recognized, and talked about him — a very small win for his species.

Bridging the Islands — wildlife crossings

People came to recognize the deathly toll that roads have on wild creatures several decades ago and began to ponder solutions to mitigate this tragedy. The thought occurred to some to build bridges instead of walls. Some communities constructed crossings specific for the use of animals that needed to safely cross our most deadly roads — from bridges for bears and migrating ungulates, to tunnels for turtles and frogs. Some communities have organized human bridges to scoop up unsuspecting frogs trying to cross a road to reach a breeding pond and safely ferrying them to the other side. European countries led the way in the 1950’s and noted a substantial increase in the populations of at-risk and endangered wildlife. Connecting island habitat reserves by bridges or tunnels makes each island effectively larger by allowing animals to migrate, increasing the chances for a healthy level of genetic diversity. The U.S. now has more than 1,500 dedicated wildlife crossings in at least 43 states, but many more are needed, for we have made many islands.

Making the Connection

If I were lucky enough to come across Gulo in the wild, I imagine him asking me questions that I wouldn’t know how to answer; Why is the snow disappearing? Can you bring it back? Where have my kin gone? Over a mere century, a blink of the geologic eye, humans have altered Earth’s biosphere to the point where we are now facing down Earth’s sixth mass extinction of species. While we have set about creating islands and degrading Earth’s environment, Gulo has simply been going about playing his role in the ecosystem as a scavenger and predator, as he has done for the past 5 million years.

How do wolverines fit into the subarctic tundra ecosystem? How would this ecosystem be affected if wolverines disappeared from it? Wolverines are generalists within their habitat, consuming a wide variety of food sources. Their overall effect on the ecosystem is not yet well understood. As with many things — it’s complex. But we do know that every living creature has an affect on the balance and overall health within their ecosystem. An excellent discussion on this topic, including a review of trophic cascades, is found in this blog post written by Rebecca, executive director of the Wolverine Foundation, in The wolverine Blog: Trophic Cascades and Some Thoughts on How Wolverines Affect the Ecosystem.

The disappearance of an apex carnivore from it’s habitat has a ripple effect throughout the food web, affecting the overall health of that community over time. None of the creatures living within the island reserves humans have created are going to disappear overnight but, without human efforts to restore and properly care for Earth’s environment, one by one they will blink out of existence, unable to find their necessities of life in a world that has always provided for them. Every influence that adds to their isolation leaves both the creatures and their habitats increasingly at the mercy of accelerating events that can sweep through a last stand quite suddenly — drought, wildfires, flooding, disease epidemics, insect outbreaks, etc. Fragmentation, the opposite of wholeness, is the enemy of everything that keeps ecosystems healthy and strong.

Just as wildlife needs connectivity between island reserves, people need to make the connection about the importance of these linkages — this habitat connectivity. If the living systems we choose to protect aren’t large and strong and interconnected, then we aren’t really conserving them. Not for the long term. By the time a species has had the unfortunate honor of being appended to the IUCN Red List, or the Endangered Species List, their chances of taking the next step to extinction is very high. The time to protect the diversity of life is when a species is thriving, and we need to ensure the habitats they are thriving in are kept healthy, resilient, and whole. All life depends on it.

References

COP15 Summary: The World Coming Together for Biodiversity

~ Carole ~ 2 Comments

The UN Biodiversity Conference including the fifteenth Conference of the Parties (COP15) recently concluded in Montreal, Canada. The main objective of this meeting was to adopt the post-2020 global biodiversity framework — a strategic vision and global roadmap for the conservation, protection, restoration, and sustainable management of biodiversity and ecosystems for the next decade. This is critically important work that I wanted to shine a light on.

The Convention on Biological Diversity includes 196 parties; every country in the world except the United States and the Holy See (the U.S. isn’t a party to the convention because Republicans, who are typically opposed to joining treaties, have blocked U.S. membership. The American delegation can only participate from the sidelines). The U.N Secretary General, António Guterres, stated in his opening remarks: “With our bottomless appetite for unchecked and unequal economic growth, humanity has become a weapon of mass extinction”. Katharine Hayhoe, chief scientist at the Nature Conservancy and prominent climate researcher.explained “Climate change presents a nearer-term threat to the future of human civilization. The biodiversity crisis presents a longer-term crisis to the viability of the human species.” Humans are responsible for driving climate change and biodiversity loss through the overconsumption of Earth’s resources.These two threats are interconnected and must be addressed together. It is important to note that we are locked into the climate we have created for the next thousands to millions of years. Every day that we continue to dump greenhouse gases into our atmosphere only compounds the severity of climate change effects that we are facing.

The planet is currently undergoing its sixth mass extinction.The cause is undeniable; humans have taken over too much of the planet and disrupted or destroyed the habitats of our plant and animal partners. Climate change and other pressures exacerbate the problem. Most of the land grab is taken for agriculture, like clearing forests to graze cattle or plant crops, or to build cities and roads. The human population just surpassed 8 billion people and per capita consumption continues to soar. The global rate of species extinction is already tens to hundreds of times higher than the average rate over the past 10 million years and is accelerating. If you are already aware of the magnitude of this species’ slaughter or have a hard time stomaching the numbers, feel free to skip this list. The data is sobering — here’s a sampling of it:

  • A million plants and animals are at risk of extinction, many within decades.
  • 75% of Earth’s land surface is significantly altered, 85% of wetlands have been lost.
  • Marine plastic pollution has increased tenfold since 1980, affecting at least 267 species, including 86% of marine turtles, 44% of seabirds, and 43% of marine mammals.
  • Nearly one-fifth of Earth’s surface is at risk of plant and animal invasions, impacting native species, ecosystem functions, and nature’s contributions to people. The rate of new invasive alien species is higher than ever and shows no sign of slowing.
  • Approximately half of the live coral cover on coral reefs has been lost since the 1870’s, with accelerating losses in recent decades due to climate change exacerbating other drivers.
  • The average abundance of native species in most major terrestrial biomes has fallen by at least 20% (mostly since 1900), potentially affecting ecosystem processes.
  • Rapid declines in insect populations is well documented in some areas, although global trends remain unknown.

In order to avoid dropping into the depths of despair and hopelessness when facing this reality, it’s helpful to focus on some of the current global efforts being made by individuals and organizations to alleviate or reverse biodiversity loss and mitigate the affects of climate change. Here are just a few examples:

  • With the help of The Nature Conservancy and Blue Bonds for Ocean Conservancy, Belize is able to restructure much of the country’s debt and generate $4 million annually for environmental protection over two decades.
  • In Canada’s far north, Inuit leaders are working to restore caribou herds that have been in steep decline.
  • The United Nations is creating a binding framework by the end of 2024 to guide the elimination of plastic pollution. It declared access to a clean, healthy, and sustainable environment a universal human right.
  • Brazilian citizens have planted over 2 million trees since 2005. Tree coverage has expanded in 36 countries between 2005 and 2020.
  • Argentina has created a new 1.6 million-acre national park incorporating a salt lake and surrounding wetlands providing needed habitat for numerous birds, mammals, amphibians, reptiles, and fish.
  • European bison are being reintroduced in Kent, United Kingdom, as part of a larger project to restore the area’s natural biodiversity.
  • A town in Japan has figured out how to reuse or recycle 80% of it’s waste. South Korea now recycles 100% of its food waste.
  • Since 2001, 195 sites around the world have been certified by the International Dark-Sky Association. These sites limit their light pollution which negatively impacts birds, animals, plants, and ecosystems.
  • Across the country, local watersheds and Land Trusts work tirelessly to conserve and restore thousands of acres of rivers, forests, and wildlife habitat.

And now, after two weeks of negotiations, the COP15 participating governments agreed to a historic deal — the Kunming-Montreal Global Biodiversity Framework (GBF). To quote Brian O’Donnell, director of the Campaign for Nature: “This is a huge moment for nature.”. The GBF consists of four overarching global goals to protect nature: 1) halting human-induced extinction of threatened species and reducing the rate of extinction of all species tenfold by 2050; 2) sustainable use and management of biodiversity to ensure that nature’s contributions to people are valued, maintained, and enhanced; 3) fair sharing of the benefits from the utilization of genetic resources, and digital sequence information on genetic resources; 4) the adequate means of implementing the GBF be accessible to all Parties, particularly Least Developed Countries and Small Island Developing States. The GBF also features 23 targets to achieve by 2030, including:

  • Effective conservation and management of at least 30% of the world’s land, coastal areas, and oceans. Currently, about 17% of land and about 8% of marine areas are protected
  • Restoration of 30% of terrestrial and marine ecosystems
  • Reduce to near zero the loss of areas of high biodiversity importance and high ecological integrity
  • Halving global food waste
  • Phasing out or reforming subsidies that harm biodiversity by at least $500 billion per year, while scaling up positive incentives for biodiversity conservation and sustainable use
  • Mobilizing at least $200 billion per year from public and private sources for biodiversity-related funding
  • Raising international financial flows from developed to developing countries to at least $30 billion per year
  • Requiring transnational companies and financial institutions to monitor, assess, and transparently disclose risks and impacts on biodiversity through their operations, portfolios, supply and value chains

Indigenous populations include about 476 million people living across 90 countries and representing 5,000 different cultures. They manage an estimated 25% of Earths land mass. Yet they are among the worlds most disadvantaged and vulnerable groups due to systemic marginalization. The GBF acknowledges the important roles and contributions of indigenous populations around the world as stewards of nature and partners in its conservation, restoration, and sustainable use.

MAKING THE CONNECTION

The UN Biodiversity Conference has done the work of pulling together the scientific data and the delegates of the world’s countries to set these ambitious, but necessary, goals. Can these lofty targets be realized? We cannot be lulled into thinking that it is now the responsibility of each government to achieve them. Hopefully, our governments will follow through on these commitments and provide the necessary financing, hold companies accountable to sustainability practices, along with enacting laws to conserve Earth’s land and waters for protection.

It is, however, imperative that everyone on earth (yes, that’s me, you, everyone) do their part to meet these goals. We cannot continue to be a part of the problem and hope that someone else will fix the disaster we are creating. Here are just a few ideas for that you can start doing immediately to do your part. Do one or two, or all of them and more — every action you take multiplies the actions others are taking, and this is where the ultimate solution lies.

  • Support and/or volunteer for organizations that conserve and restore lands
  • Reduce or eliminate meat consumption, particularly beef. Adopt a more plant-based diet
  • Create a nature-friendly garden; add native plants including flowering plants that pollinators love, eliminate pesticide use, provide a clean source of water for birds, insects, amphibians. Join the Backyard Habitat Certification Program!
  • Commit to your next vehicle purchase being electric or hybrid
  • Talk to your friends and family about what you are doing to mitigate climate change and biodiversity loss
  • Reduce food waste, compost, grow your own vegetable garden
  • Add solar panels to your home, if possible, or support green energy.
  • Avoid, as much as possible, buying anything plastic. Lots of companies are now producing quality products that are not packaged using plastic — look for them online. Skip the plastic produce bag at the grocery store and bring your own reusable grocery bags to the store with you
  • Buy less and buy wisely — local, seasonal, organic, Fair Trade, Rainforest Alliance, renewable materials, recycled content, etc

REFERENCES

  1. “COP15 ends with landmark biodiversity agreement”. (Dec. 20, 2022). Retrieved from: unep.org
  2. “The United Nations Biodiversity Conference”. (December 2022). Retrieved from: cbd.int
  3. “Summary for policymakers of the global assessment report on biodiversity and ecosystem services“. (2019). Retrieved from: zenodo.org
  4. Einhorn, C. and Leatherby, L. (Dec. 9, 2022). “Animals Are Running Out of Places to Live” . Retrieved from: nytimes.com
  5. Janicki, J., Daigle, K., and Kiyada, S. (Dec. 23, 2022). “On the Brink”. Retrieved from: reuters.com
  6. Einhorn, C. (Dec. 20, 2022). ” Nearly Every Country Signs On to a Sweeping Deal to Protect Nature”. Retrieved from: nytimes.com
  7. Grandoni, D. (Dec. 19, 2022). “Nations promise to protect 30 percent of planet to stem extinction”. Retrieved from: washingtonpost.com
  8. “World | Points of Progress”. Retrieved from: csmonitor.com
  9. Dunne, D. (July 21, 2022). ” Explainer: Can climate change and biodiversity loss be tackled together?”. Retrieved from: weforum.org

Lessons from the Rocks

~ Carole ~ 1 Comment

What do you think of when you look at a rock? Have you ever picked up a rock that caught your eye and decided to keep it for yourself? What is tugging at you to do that? When I pick up an interesting rock or gaze at a road cut that beautifully exposes the layers of rock, often twisted and folded — what I like to call “tortured rock” — my first thought is usually “What’s your story?”.

This post is a bit different from my past posts. I’m reflecting on just a few of the things I’ve learned by observing, studying, and appreciating geology and rocks. My hope is that it sparks in you the same kind of reflection of what you have learned from observing the world around you. If you love to observe and identify birds, what have you learned from that process other than the names and identifying features of the birds? What connections can you make? If you have additional thoughts on what you have learned from looking at rocks, landscapes, and studying geology please share them in the comments below.

HOW TO BE A DETECTIVE

Much of the study of Geology involves tapping into creative and higher thinking processes to solve the riddle of the rocks. Just like how our own life’s memories become spotty and sometimes warped, with certain events recalled in sharp detail and others either skewed from reality or missing altogether, the rock record displays chapters of the Earth’s life that are sometimes clearly understood (a quick, easy read), sometimes altered (a convoluted mystery), and then there are chapters that are either hidden from view or lost altogether (banned or burned books). The further back in time you look, the less information is available due to billions of years of erosion; you have to be a good detective to uncover the clues and piece together the story of Earth’s history.

With the current rapid retreat of glaciers and melting ice caps, more chapters of Earth’s history are being revealed to us. The new information now available for study may lead to new insights into the Earth’s past. It’s like finding an old photo book from your childhood that had been lost, now calling up old memories — “Oh! I remember that vacation now, but who is that guy standing next to dad?”.

BROADENING YOUR PERSPECTIVE

The geologic timescale and thinking big…really big

As a visual learner, I like seeing spatial representations of the earth’s geologic history. One of the best I’ve seen is located at Fossil Butte National Monument in southwest Wyoming (a place well worth the visit!). The display starts at the beginning of the long road that leads up to the visitor center with a sign indicating the formation of the Earth, approximately 4.54 billion years ago. The timeline is set to scale, with every 9 inches equaling 1 million years of time. As you drive the road toward the visitor center, major geologic and biologic events are displayed — oldest known rocks at 4.055 billion years, photosynthesizing bacteria at 3.7 billion years, oxygen in oceans at 2.5 billion years, sponges and Earth covered in ice at 635 million years, jellyfishes and protective ozone at 600 million years — with a lot of unmarked space between the signs. At the parking area it continues, the signs getting ever closer — trilobites at 520 million years, Gondwana continent and C02 at twenty times today’s level at 500 million years, mass extinction (57% of genera) during the Silurian period, arthropods on land and oxygen at today’s level at 420 million years, mass extinction (83% of genera) and the Siberian Traps (flood basalts) during the Triassic period — the signs placed every few feet as you walk toward the building. At the visitor center, the timeline continues around an outside deck with signs even closer together — grasses and Rocky Mountains at 70 million years, hominid ancestors and the San Andreas fault come in together, the Pleistocene epoch ends with the first eruption of the Yellowstone caldera, and ending in the Holocene Epoch with the appearance of Homo sapiens and the beginning of recorded history. — the signs now very close together and sometimes piled on top of one another, like an overcrowded bookshelf.

It’s difficult for us humans to keep this long-term perspective of geologic time in mind as we make the decisions of today. Our individual minds, of course, only hold the memories of our own lifetimes along with some of the anecdotal stories of our known ancestors. However, we are often better served if we can take a giant step back from current affairs and telescope our minds back into the geologic past in order to get a clearer sense of where we are headed in the future.

CHANGE HAPPENS

Climate change and mass extinctions

As the saying goes, “the only thing you can count on is change” (quote attributed to Patti Smith). The rate of change to Earth’s geomorphology and communities of life happens within a very broad time span; either extremely slowly over very long periods of time (the cooling of a magma chamber, the building of a mountain range), quite suddenly (volcanic eruptions, earthquakes, landslides), or somewhere in between (slow earthquakes, evolution). Most of the changes to life on Earth are a result of climactic changes that stem from both geologic and astronomical processes.

The geologic record holds clues to ancient climactic tipping points that can help inform the course of our climactic warming and mass extinction event currently underway. We see evidence of the most recent glacial periods in our current landscape in the rocks and sediment glaciers left behind, and how these masses of ice cut into the underlying rock leaving behind U-shaped valleys. Evidence of older ice ages is found both in ice and sediment cores as well as in the fossil record, showing where various species of animals migrated in order to escape the ice and cold.

There have been 6-7 major mass extinctions on Earth (with the next underway now) and another 20 minor extinction events. The major extinctions, which terminated between 35-57% of all genera and 75-95% of all species, have all been caused by catastrophic events that suddenly changed the composition of Earth’s atmosphere which lead to rapid atmospheric warming (with one exception that involved rapid cooling). The geologic evidence points to events that disrupted the carbon cycle and carbon content in the atmosphere, such as extremely large meteor impacts and major volcanic eruptions that impacted the entire globe. Another notable commonality in these events is rapid changes in ocean chemistry leading to acidification and devastation to calcite-secreting organisms. The current mass extinction event is being caused by human activities that are (relatively) suddenly changing the climate by imparting too much CO2 into the air as well as causing habitat fragmentation by destruction of nature and severing the critical connections in food webs. All past extinctions were followed by a period of time — hundreds of thousands to millions of years — when microbes alone thrived while the rest of the biosphere struggled to make a comeback. None of the mass extinctions can be fully attributed to a single cause; all involved rapid changes in several geologic systems at one time and involved many of the culprits we are currently familiar with — greenhouse gases, carbon-cycle disturbances, ocean acidification.

Minor mass extinctions are also caused by global warming or cooling events. It has been shown that Ice Ages have occurred every 41,000 years for the past one to three million years. A century ago, a Serbian scientist, Milutin Milankovitch, hypothesized, and later proved through mathematics, that the long-term, collective effects of changes in Earth’s position relative to the Sun are a strong driver of long-term climate and are responsible for triggering the beginning and end of glaciation periods (Ice Ages). He showed how three types of Earth’s orbital movements affect how much and where solar radiation reaches the Earth’s atmosphere. The three orbital cycles are:

  1. Eccentricity: the shape of the Earth’s orbit changes from nearly circular to slightly elliptical on a 100,000 year cycle.
  2. Obliquity: the angle of the Earth’s axial rotation and the cause of Earth’s seasons. Over the last million years, the Earth’s obliquity has varied between 22.1 and 24.5 degrees with respect to the Earth’s orbital plane which affects how extreme the seasons are. Larger tilt angles favor periods of deglaciation. We are currently at an angle of about 23.4 degrees. The obliquity cycle spans about 41,000 years.
  3. Axial Precession: The Earth does not spin perfectly centered on its axis but wobbles, like a slightly off-center spinning top. This is due to tidal effects caused by gravitational forces from the Sun and the Moon that cause the Earth to bulge at the equator. The cycle of axial precession spans about 25,771.5 years.

The small changes resulting from these three cycles operate together and separately, and in conjunction with other Earth processes, to influence Earth’s climate over very long timespans. Milankovitch created a mathematical model to calculate differences in solar radiation at various Earth latitudes along with corresponding surface temperatures. He calculated that Ice Ages occur at approximately every 41,000 years — subsequent research on deep sea sediment cores and ice cores from Greenland and Antarctica have confirmed this cycle from between one to three million years ago. However, starting about 800,000 years ago, the cycle of ice ages lengthened to 100,000 years matching Earth’s eccentricity cycle. Various theories have been proposed for this transition yet there is no clear explanation. Research continues to better understand the mechanisms that drive Earth’s rotation and specifically how Milankovitch cycles combine to affect climate, but Milankovitch’s theory is well-accepted in the scientific community.

Our atmosphere has undergone at least four major changes in composition since Earth’s beginning. The story of the atmosphere is connected with the story of life on Earth; life itself is responsible for our modern atmosphere, generally keeping a stable balance of elements, but occasionally the rock record shows us there were times of atmospheric revolution and ecological catastrophe. We have a direct record of ancient air for the past 700,000 years from gas bubbles trapped in ancient snow which has been preserved as polar ice. For longer timescales, the rocks reveal to us the story of ancient air by providing several clues; the abundance of water, the evolution of life forms, and the emergence of free oxygen (O2) in the atmosphere — evident both in the fossil record and the appearance of iron formations. The appearance of O2 in the atmosphere began with the appearance of cyanobacteria and had such an impact on Earth’s geochemistry that it is named “The Great Oxidation Event” or GOE. The availability of O2 changed the chemical interactions between rainwater and rocks on land, altering the composition of lakes, rivers, and groundwater. The sedimentary rock record shows a change in rock types with more oxide minerals being present. The ozone layer established and shielded Earth’s surface from the ravages of ultraviolet radiation from the Sun, and the elemental exchange opportunities led to a strategic symbiotic merger —a tiny biologic structure that had learned to process oxygen, a mitochondrion, joined with a larger cell that would eventually lead to plants and animals.

Balance and tipping points

If you’ve read Malcolm Gladwell’s book The Tipping Point then you probably already have a good understanding of this concept. In fact, I think it is because of his book that this term has become fairly commonplace and well-understood. Geology offers some great examples of tipping points, again occurring over a broad time span. We can directly observe or experience sudden tipping point events such as avalanches, landslides, and earthquakes. These occur as a basic function of physics. In avalanches and landslides, for example, gravity wins when the forces acting on a slope exceed the strength of the material holding the slope in place. The Earth’s tectonic plates are always slowly (think geologic time slow) moving in different directions which, over time, builds friction in the rocks. An earthquake happens when the stress on the rocks reaches a tipping point and suddenly releases along a fault line allowing the rocks to slide past one another. Balance is the steady state where time passes in relative equilibrium. Chaos ensues when things are out of balance and change happens suddenly. Earth and nature are always working to restore balance; our collective humanity would do well to learn how to assist with this rather than continue to create tipping points.

Earth recycles

Rocks and landscapes that we can either hold in our hand or observe from a distance may be extremely old but they are not static; instead of simply “being” they are always in the process of “becoming”. The formation, movement, and transformation of the three main rock types (igneous, sedimentary, and metamorphic) are a product of Earth’s internal heat and pressure from tectonic processes, along with the effects of water, wind, gravity, and biological actions. Each rock type is altered when it is forced out of its equilibrium state. It’s a beautiful, 100% no waste system of rock recycling— all elements either re-melted and made into new crystals or re-organized and morphed into new shapes and textures, and all rocks participate in the process. Contrast this with our production of plastic products, now observable collecting in mass quantities, from microscopic to large, absolutely everywhere on Earth — land, oceans, rivers — wreaking havoc on all life forms.

ART IS EVERYWHERE

If you look up the word “art” in a dictionary, you’ll be presented with all sorts of definitions that center around the production of some piece of work (painting, sculpture, drawing, etc) that was created by a human using a skill, an activity, or a method. I would argue that the creation of art is not singularly a human activity; art can be found everywhere in nature, including the rocks. My own definition of art may be: “A creation to behold which inspires awe, wonder, or simply a desire to linger and enjoy the positive emotions felt by the beholder.” The creator may be anyone or anything, including Mother Nature. Here are some examples of what I would consider art created by Mother Nature using rocks as her medium. Certainly a person took these photographs and lent their own vision of composing the scene to represent the beauty yet the same, if not more intense, feelings can be felt when viewing these areas in person.

Scroll through Dr. Marli B. Miller’s photo gallery to see examples of rock artistry at: https://geologypics.com/geological-item/instagram-pics/?undefined. Marli is a geology researcher and senior instructor at the University of Oregon. She is the author of Roadside Geology of Oregon, Second Ed.

Scroll through the photos above for some other examples of:

  1. Colors — Earth’s palette (Blue Basin, Oregon)
  2. Shapes — Rock molded by Earth’s hands: (Columnar basalts, Iceland)
  3. Patterns — the diverse layering and arrangements of rocks (Paria Canyon – Vermillion Cliffs Wilderness Area, Arizona)
  4. Fossils — the awe of ancient life, preserved in rock (Ammonites)
  5. Crystals — the beauty and variety of elemental arrangements (Amazonite and smokey quartz)
  6. Creation of new rock — the wonder of Earth’s tectonic processes (Cinder cone, Canada)
  7. Balancing acts — Rock defying gravity (Globe Rock, California). Why do humans like to create stacks of balancing rocks?

Going micro: zooming in on the details

A close friend and I like to take geology-focused road trips to enjoy and learn about the geology of our chosen area. After several trips together, I began to notice that there was a pattern to how each of us first “looked” at the rocks in an outcrop. I would stand back to take in the overall picture in front of us, then start zooming in to observe larger structures and smaller details within the outcrop — see the cross-bedding here, that looks like a fault over there. Starting to read the story held within the rocks. My friend likes to immediately focus in on the unique structure and beauty contained in individual rock hand samples. I like to say “she goes micro while I go macro”. Our different approaches are very complementary for each other. I make sure she sees and understands the larger geologic story while she takes me into the unique beauty held within an individual rock.

It’s the beauty held within a rock sample that leads my friend to “go micro” — their diverse colors, shapes, luster, and arrangements of minerals, and the reason why so many people are drawn to pick up and take a rock home with them. It’s one of the many ways we can learn to appreciate the beauty in nature. Whether looking at an outcrop of folded and mashed-up rock layers, an expansive landscape of glaciated granite peaks and valleys, or the stunning array of colors in a hand sample of jasper, the rocks are teaching us to recognize and appreciate the beauty found in nature.

SAFEGUARD YOUR VALUABLES

Water is Life

Rocks demonstrate the importance of sequestering precious resources. They serve as a great storage container for our life-giving water. The average water molecule stays in the atmosphere for about nine days; the residence time of water in the largest lakes is up to 200 years; deep groundwater may be stored in underground aquifers for 10,000 years. The amount of groundwater in an aquifer fluctuates over time depending on water input and outflow, The aquifer fills, or recharges, as surface water filters down through soil and rock and depletes as it is pumped back to the surface for human consumption or migrates to another region in a subsurface flow. Currently, climate change has shifted global weather patterns that have led to both drought and flooding, altering the amount of recharging to aquifers, while humans continue to draw from the aquifers at the rate we have become accustomed to.

The family jewels

The Earth has created many elements and minerals that humans have found irresistible, however we have yet to learn to respect and use these resources with care and conservation. There are places on Earth that some indigenous groups hold sacred, yet others come along in disrespect and destroy by mining, logging, or paving over. A majority of the man-made items you can reach out and put your hands on right now, including the computer I am writing on, are available to you thanks to the mining of Earth’s precious elements and minerals. The top 10 minerals extracted for human use are: copper, feldspar. lithium, silver, gold, iron ore, nickel, beryllium, and molybdenum. As of 2017, the U.S. government keeps a list of 35 elements and minerals that are “…essential to the economic and national security of the United States…the absence of which would have significant consequences for the economy and national security.” Our human lives as we know them are dependent on these 35 elements and minerals. They bring us batteries, pesticides, cement, steel, gasoline, integrated circuits, LED’s, fertilizers, fireworks, magnets, solar panels, nuclear fuel, glass, lubricants, microchips, medicines, paint, plastics, and oh-so-much more. Some of these minerals are found only in low concentrations making them difficult and expensive to mine. About 98% of the Earth’s crust is made up of only eight elements: oxygen, silicon, aluminum, iron, calcium, sodium, potassium, and magnesium. Everything else on the periodic table makes up the remaining 2%. It is estimated that every person in the U.S. will use more than three million pounds of rocks, minerals, and metals during their lifetime (!!!) — that’s a human lifetime, as compared to the time it took for the minerals to form (again… geologic timescale). Who do those materials belong to? Who is profiting from extracting them? Whose habitats are destroyed in the process of extraction?

Our lesson here from the rocks is that Earth’s precious resources, like clean water, clean air, precious elements, and minerals, are in limited supply and belong to all beings that live in community on the planet. They must be treated with the utmost care in a sustainable way for the benefit of all.

MAKING THE CONNECTION: Our place on earth

I’ve picked up from my desk one of the many rocks I’ve collected from somewhere during my travels here and there. It’s a piece of grey sandstone a bit larger than the size of a quarter — a good pocket rock. Several thin lines of white quartzite run through the sandstone and a thicker section of quartzite caps the “top” of the stone. It’s a well-polished stone — probably picked up off the Oregon coast — mostly round, but more tapered under the thicker layer of quartzite. It’s this taper with the thicker quartzite cap that makes me always want to hold it with this part oriented up. I guess it reminds me of a snow-capped mountain peak…maybe a clue to it’s origin. If I hold it just right in the light and look closely, tiny grains of quartz wink back at me. When I look at it through my microscope, the individual grains of quartz, feldspar, and biotite or hornblende come into focus. As I hold it in my hand and focus my attention on it, it starts to tell me it’s story; glacial erosion of an old Cambrian granite batholith, further weathering and transport by river action, deposition, burial, and millions of years of pressure and heat causing compaction and some dissolution of the mineral grains, cementation by fluids charged with dissolved minerals. The quartzite veins formed during this stage when the rock fractured and silica-rich fluid filled the fracture zones which, after more time, crystalized. This rock had a cozy, stable home for a long time while this process was happening, but at some point tectonic forces pushed and shoved the rock back to Earth’s surface where it eventually broke free and tumbled once again into a river where a series of flooding events picked it up and carried it off to the ocean. Here it was tumbled about by wave action, further smoothing the edges and wearing away the sandstone until one day I happened to come along to spy it and feel inclined to pick it up, admire it, and take it home with me.

From Timefulness by Marcia Bjornerud: “Young rocks communicate in plain prose, which makes them easy to read, but they typically have only one thing to talk about. The oldest rocks tend to be more allusive, even cryptic, speaking in metamorphic metaphor. With patience and close listening, however, they can be understood, and they generally have more profound truths to share about endurance and resilience.”

The most important lesson we may learn from our observations and study of geology is to be able to take the long view of Earth and life through time. The ability to do this allows us to be able to confront issues we currently face against the backdrop of the bigger picture of the stories of life through time; the recurring themes and chapters, the evolving cast of characters, sudden drama, and clear-eyed solutions. Many humans have forgotten the value of nature and the role we play in nurturing nature and working respectfully together with all forms of life that share the resources of this planet. When we become familiar with the narratives of natural history, we come to feel a connection with everything on the planet. The rock record reveals how our bodies are part of a continuum made from the raw materials of the earth — our bones made up of the calcium and phosphorus minerals derived from rock, our blood a distant memory of seawater — we are part of an unbroken chain of living organisms that stretches back to the very earliest days of our planet. As Earthlings, we are fully native to Earth.

References:

  • Bjornerud, M. (2021). Becoming Earthlings. Kinship: Belonging in a World of Relations, Vol. 01 Planet, pp 13 – 20.
  • Bjornerud, Marcia, Timefulness: How Thinking Like A Geologist Can Help Save The World, New Jersey: Princeton University Press, 2018, print.
  • Strauss, B., “The Earth’s 10 Biggest Mass Extinctions”, Feb 02, 2020, Retrieved from www.thoughtco.com
  • Brovkin,V., et.al., “Past abrupt changes, tipping points and cascading impacts in the Earth system”, July 29, 2021, Retrieved from USGS Publications Warehouse
  • “List of Extinction Events”, Retrieved from en.Wikipedia.org
  • Buis, A., “Milankovitch (Orbital) Cycles and their role in Earth’s Climate”, Feb 27, 2020, Retrieved from www.climate.nasa.gov
  • “Understanding Global Change”, Retrieved from www.ugc.berkeley.edu
  • “Groundwater Storage and the Water Cycle”, June 18, 2018, Retrieved from www.usgs.gov
  • Alden, A., “What is Sandstone?”, Aug. 13, 2019, Retrieved from www.thoughtco.com
  • Motavalli, J., June 19, 2010, Retrieved from www.cbsnews.com
  • King, H.M., “REE — Rare Earth Elements and their Uses”, Retrieved from www.geology.com
  • Conca, J., Nov. 19, 2019, “35 Minerals That Are Critical To Our Society”, Retrieved from www.forbes.com
  • Silva, J., July 21, 2016, “Top 10 Minerals Mined in the U.S.”, Retrieved from www.blog.midwestind.com
  • “Rocks and Minerals: Everyday Uses”, Retrieved from www.mnch.uoregon.edu

The Mighty Diatom and the Air we Breathe

~ Carole ~ 4 Comments

Raise your hand if you know what a diatom is. Don’t feel bad if you didn’t raise your hand; you are in the majority of people around you. Maybe you recall your 7th grade biology teacher mentioning them, but you never quite understood what they were. I say it’s high time we understood them a bit better given that these mighty diatoms are responsible for producing about 50% of the oxygen we breathe through that amazing process — photosynthesis. Yes, something that is microscopic and virtually unknown by most people is responsible for a critical element, O2, that is vital to sustaining life on earth.

DEFINITIONS:

  • Micron: Also known as a micrometer — a unit of length equal to one millionth of a meter.
  • Organelles: Specialized structures that perform various jobs inside cells. Literally “little organs”; just as familiar organs (heart, lungs, kidneys, etc.) serve specific functions to keep an organism alive, organelles serve specific functions to keep a cell alive.
  • ATP: Adenosine Triphosphate — an organic compound that provides energy to drive many processes in living cells. It is found in all known forms of life. The human body recycles its own body weight equivalent in ATP every day.
  • NADP+: Nicotinamide adenine dinucleotide phosphate — a cofactor used in anabolic reactions (like the Calvin Cycle). NADPH is the reduced form of NADP+.
  • Stroma: Tissue that serves a structural or connective role in a cell.
  • Plankton: Includes a diverse collection of organisms found in water or air that cannot propel themselves against a current. Some examples include bacteria, algae, protozoa, plant spores, pollen. Most are microscopic however some are quite large, including jellyfish. They are a crucial food source for many small and large aquatic organisms.

What are Diatoms?

Diatoms are single-celled algae found in the oceans, waterways, and soils of the world. They are the only organism on the planet with cell walls composed of transparent, opaline silica. They are quite beautiful and unique when viewed under the microscope displaying an amazing kaleidoscope of shapes. I’ve added a few pictures below. You can also check out some of the references below for good pictures. Their size ranges from 2 – 500 microns with the largest being about the width of a human hair. They constitute about half the organic matter found in the ocean. There are an estimated 20,000 – 2,000,000 different species of diatoms with more being discovered every year. Various species have developed structural adaptations to be able to move about or attach themselves to rocks or other organisms. This may allow them to stay afloat or resist wave action as needed depending on their environment. Diatom species are particular about the quality of water they live in.

What is Photosynthesis?

Like plants, diatoms and other algae use sunlight to transform water and carbon dioxide into oxygen and simple carbohydrates during the process known as photosynthesis — didn’t your 7th grade teacher also mention something about photosynthesis during biology class? Considering that photosynthesis is essential for the existence of all life on earth, it seems important to have a basic understanding of that process. Here’s my very simplified explanation of how photosynthesis works.

The photosynthesis process takes place in cell organelles called chloroplasts. Chloroplasts contain a green-colored pigment call chlorophyll — chlorophyll is responsible for the green coloration in plant leaves. Phototsynthesis occurs in two stages: a light dependent reaction and a light independent reaction (the Calvin Cycle). The light dependent reaction occurs in the thylakoid cells where energy from sunlight is converted to ATP and NADPH which is then used to power the Calvin Cycle. During the light reaction, the hydrogen from water is used and oxygen is produced. The light independent reaction, or Calvin Cycle, is also referred to as the carbon-fixing reaction. This reaction occurs in the stroma of the chloroplast. Water and carbon dioxide, along with the ATP and NADPH are converted to sugar (glucose) molecules that feed the plant.

Diatoms in the Great Lakes

Diatoms comprise the bottom rung of an aquatic food web. Zooplankton (small protozoans that feed on other plankton) feed on algae, smaller fish feed on zooplankton, bigger fish feed on smaller fish, and on up the food chain. Diatoms are busy photosynthesizing year round, even in lakes covered by both ice and snow. Diatoms need just the right balance of depth and sunlight to do their thing. If they sink too deep they don’t get enough sunlight, and if they are higher in the water column they can get burned. Snow may be protective against too much sunlight. Without diatoms to support zooplankton during the winter months, the lakes productivity for the rest of the year suffers.

Researchers have found that, over the past 115 years, individual diatoms are getting smaller and this decrease in size seems related to climate change. As the lakes become warmer, the bigger diatoms sink and are unable to harvest adequate sunlight to photosynthesize. The trend is toward smaller diatoms and fewer of them. Additionally, invasive species of mussels that have been introduced into the Great Lakes have caused the numbers of diatoms to plummet; mussels can filter the amount of water in Lake Michigan (removing plankton, including diatoms) in about a week or less. In Lake Erie, diatom numbers have plunged 90% in the last 35 years. A loss of this magnitude in a keystone species should be alarming to everyone, but again, think about how many people even know what a diatom is.

How do Diatoms Reproduce?

I’m suspecting you remember more about human reproduction from your 7th grade Biology teacher than diatom reproduction, but hang in here…this is fascinating!

Diatoms reproduce by both an asexual and a sexual process. The asexual process is primary and occurs by binary fission to produce two new diatoms with identical genes. You can see from the diagram below that the frustule splits to form two daughter cells; one with the larger half of the frustule (the epitheca) and one with the smaller half (the hypotheca). The diatom that receives the hypotheca remains smaller than the parent. With continued asexual reproduction, the average cell size of the diatom population decreases.

In order to restore the diatom population to it’s original cell size, sexual reproduction occurs through meiosis. A special structure, called an auxospore, is formed. This is a unique type of cell that possesses silica bands rather than a rigid silica cell wall. This unique cell allows the cell to expand to it’s maximum size. Once an auxospore divides by cell division, it produces a normal diatom cell which then continues to get smaller with each asexual cell division.

Diatoms in the Fossil Record

The silica cell walls of diatoms are inorganic, so they do not decompose. These structures are found in the fossil record back as far as the early Jurassic (~185 million years ago). It has been suggested that the evolutionary ability of these organisms to produce a resting stage (the Auxospore) along with the ability to photosynthesize had an adaptive advantage over other organisms during intense climatic, tectonic, and geochemical changes that led to a mass extinction period close to the Permian-Triassic boundary (~251 million years ago). After the mass extinction event, many niches (habitats) in the aquatic realms opened up and diatoms appear to have diverged at this time and evolved to develop silicic cell walls. Thus, they are found in greater abundance in the fossil record since this time. The fossil record shows diatom diversity to be very sensitive to global temperature. Warmer oceans, particularly warmer polar regions, have in the past been shown to have substantially lower diatom diversity. Thus, future warmer oceans could, in theory, result in a significant loss of diatom diversity although it is unclear how quickly this change would happen.

MAKING THE CONNECTION:

I hope I have led you to a greater understanding and appreciation of what diatoms are and the important role they play in sustaining life on earth. By studying the fossil record, we know diatoms have been with us for millions of years and have evolved over time as climactic and geochemistry conditions changed. We also know that in order for organisms to adapt to changing conditions (evolve), changes need to occur relatively slowly. We can observe today how local conditions in lakes and oceans are affecting diatom populations. We can also acknowledge that there is a lot more to learn about how diatoms adapt, and how quickly, to changing conditions. One thing seems clear — we should be showing more gratitude and respect for these amazing organisms. So the next time you take a big gulp of air (like now) remember to give thanks to the mighty diatoms who work tirelessly to keep us supplied with oxygen!

REFERENCES: