Tag Archives: biodiversity

Large Igneous Provinces and mass extinction

Ars Technica has an article on Large Igneous Provinces, which are volcanic eruptions so large (occurring every 15 million years or so on average) they are thought to be the main culprit behind most mass extinctions. Lava and toxic gas can be bad but are not enough to explain mass extinction. They can actually cause large-scale global cooling on a short time scale (a decade or so) due to particulate emissions, but that effect also is not enough to explain mass extinction. The way they are thought to cause global mass extinction this is by burning underground fossil fuels on an enormous scale, causing catastrophic climate change that species cannot adapt to (including global warming, sea level rise, and ocean acidification, which kick in after the shorter-term cooling effect has run its course, and last a lot longer).

I was also wondering about volcanic activity versus comet and asteroid strikes. The article addresses that too:

Debate over what caused these factory resets of life has raged ever since Cuvier’s time. He considered them to be caused by environmental catastrophes that rearranged the oceans and continents. Since then, a host of explanations have been proposed, including diseasesgalactic gamma raysdark matter, and even methane from microbes. But since the 1970s, most scientists have considered the likely root cause to be either asteroid impacts, massive volcanic eruptions, or a combination of both.

Those asteroid (or comet) impacts have captured the public imagination ever since 1980, when Luis and Walter Alvarez found global traces of iridium, which they inferred to be extraterrestrial, at the geological boundary that marked the disappearance of the dinosaurs. The identification of the Chicxulub impact crater in Mexico soon after sealed the deal. Impacts have been proposed to explain other mass extinctions, but there’s very little actual evidence to support those links. In the words of researchers David Bond and Stephen Grasby, who reviewed the evidence in 2016: “Despite much searching, there remains only one confirmed example of a bolide impact coinciding with an extinction event…”

Volcanism, on the other hand, has coincided with most, if not all, mass extinctions—it looks suspiciously like a serial killer, if you like.

According to the article, the rate of fossil fuel burning is similar to what humans are doing now. So it follows that natural ecosystems could collapse this time too. That would be a catastrophe in itself, but how resilient can our species and food production systems be compared to all the others that have come and gone before us?

Sounding the alarm on biodiversity

What’s the elevator pitch to convince a skeptic that biodiversity is important? To people who value nature for its own sake and believe it is immoral to destroy it, maybe it seems as though the pitch should not be needed. But it’s needed, considering the difficulties communicating the practical/economic case against global warming when that case should be fairly obvious (reliability of the food supply; cost of food, energy, and water; cost to protect, relocate or abandon coastal cities; impacts of extreme weather, drought and fire inland).

Of course, the practical/economic case to fight biodiversity loss has to do with how much our civilization relies on free ecosystem services, and has neither the level of technology nor wealth to replace them in the near term. I believe many people will respond to the ethical case too, and more would if we emphasized ethics more in children’s education. But this paragraph is already too long for an elevator pitch now, isn’t it.

Here are a couple articles that talk about bolstering both the science and the communications.

http://www.cell.com/trends/ecology-evolution/fulltext/S0169-5347(17)30263-X

https://www.project-syndicate.org/commentary/climate-change-biodiversity-loss-by-robert-watson-2-2017-11

 

 

disappearing bugs

This surprising study from Germany raises the possibility that a catastrophic loss of insects is occurring and that it could lead to ecological collapse.

More than 75 percent decline over 27 years in total flying insect biomass in protected areas

Global declines in insects have sparked wide interest among scientists, politicians, and the general public. Loss of insect diversity and abundance is expected to provoke cascading effects on food webs and to jeopardize ecosystem services. Our understanding of the extent and underlying causes of this decline is based on the abundance of single species or taxonomic groups only, rather than changes in insect biomass which is more relevant for ecological functioning. Here, we used a standardized protocol to measure total insect biomass using Malaise traps, deployed over 27 years in 63 nature protection areas in Germany (96 unique location-year combinations) to infer on the status and trend of local entomofauna. Our analysis estimates a seasonal decline of 76%, and mid-summer decline of 82% in flying insect biomass over the 27 years of study. We show that this decline is apparent regardless of habitat type, while changes in weather, land use, and habitat characteristics cannot explain this overall decline. This yet unrecognized loss of insect biomass must be taken into account in evaluating declines in abundance of species depending on insects as a food source, and ecosystem functioning in the European landscape.

I knew about the frogs, elephants, tigers, bees, and loss of larger animal species and biomass in general, but I hadn’t really heard this idea that insects are disappearing. I can see a silver lining to this – I can’t really create elephant or tiger habitat around my house, and frog habitat is a little tough, but insects – I can actually help the little guys. On a larger scale, there is the question of green infrastructure – can we deliberately design habitats in cities, larger reserves, and corridors connecting them to support as much ecological function as we can? I think so, but I don’t think our public officials, engineers, urban planners, scientists, and others in a position to do this are tuned into the issue or even very open to hearing about it.

Aichi biodiversity targets, Sustainable Development Goals and the Protected Planet report

The Aichi Biodiversity Targets were adopted by the parties to the Convention on Biological Diversity in 2010, and at least some aspects of them (slightly confusing to me) were incorporated in the Sustainable Development Goals adopted by the UN in 2015. In short, my understanding from a quick skim is that the target is to protect 17% of land area. The current status is reported in a Protected Planet report that the UN produces every two years. (Disclaimer: I could easily have some details wrong here.)

In terms of the representation element of Aichi Biodiversity Target 11, less than half of the world’s 823 terrestrial ecoregions have at least 17% of their area in PAs and only one third of the 232 marine ecoregions have at least 10% of their area protected. Less than 20% of Key Biodiversity Areas are completely protected, and therefore further efforts are needed to expand PA systems to ensure that the global PA estate adequately covers areas important for biodiversity and the provision of ecosystem services to people.

de-extinction

Here’s the Amazon description of a new (to me) book called Bring Back the King: The New Science of De-extinction.

If you could bring back just one animal from the past, what would you choose? It can be anyone or anything from history, from the King of the Dinosaurs, T. rex, to the King of Rock ‘n’ Roll, Elvis Presley, and beyond.

De-extinction, the ability to bring extinct species back to life is fast becoming reality. Around the globe, scientists are trying to de-extinct all manner of animals, including the woolly mammoth, the passenger pigeon and a bizarre species of flatulent frog. But de-extinction is more than just bringing back the dead. It’s a science that can be used to save species, shape evolution and sculpt the future of life on our planet.

In Bring Back the King, scientist and comedy writer Helen Pilcher goes on a quest to identify the perfect de-extinction candidate. Along the way, she asks if Elvis could be recreated from the DNA inside a pickled wart, investigates whether it’s possible to raise a pet dodo, and considers the odds of a 21st century Neanderthal turning heads on public transport.

Pondering the practicalities and the point of de-extinction, Bring Back the King is a witty and wry exploration of what is bound to become one of the hottest topics in conservation if not in science as a whole in the years to come.

biodiversity and ecosystem services in decisions

Here’s an “open-source software tool for integrating biodiversity and ecosystem services into impact assessment and mitigation decisions“.

Governments and financial institutions increasingly require that environmental impact assessment and mitigation account for consequences to both biodiversity and ecosystem services. Here we present a new software tool, OPAL (Offset Portfolio Analyzer and Locator), which maps and quantifies the impacts of development on habitat and ecosystem services, and facilitates the selection of mitigation activities to offset losses. We demonstrate its application with an oil and gas extraction facility in Colombia. OPAL is the first tool to provide direct consideration of the distribution of ecosystem service benefits among people in a mitigation context. Previous biodiversity-focused efforts led to redistribution or loss of ecosystem services with environmental justice implications. Joint consideration of biodiversity and ecosystem services enables targeting of offsets to benefit both nature and society. OPAL reduces the time and technical expertise required for these analyses and has the flexibility to be used across a range of geographic and policy contexts.

more on China’s “ecological civilization”

The United Nations has a new report on China’s “ecological civilization” plan. What seems notable is that it takes an urban and regional planning framework, then weaves in goals related to environmental quality and sustainable agriculture. There are also a few targets related to habitat and biodiversity conservation. It’s a good vision and contains all the right rhetoric.

instrinsic vs. utilitarian value of nature

This thoughtful opinion piece in Trends in Ecology and Evolution talks about resolving conflicts between moral and economic arguments for conservation.

Biodiversity exists at multiple levels of organization, including at the levels of genes, populations, species, and ecosystems [11]. Although it might be argued that intrinsic value is associated with all levels of biological organization, this interpretation is of no practical use for planning and decision-making. If all levels of biological organization have equal intrinsic value, and if all species are regarded as having equal intrinsic value, then the implication is that no harm can be done in any way to any component of biodiversity [I don’t quite follow this last sentence…]. The concept of intrinsic value applied equally to all of nature therefore offers no way to prioritize and points only toward a halt to human progress because most human developments impact on nature to some degree. In practice, then, intrinsic value is commonly associated with certain species and ecosystems…

Species conservation and the beauty of nature are reasons for conservation commonly associated with intrinsic and non-use values. For instance, it can be regarded as morally right to maintain the existence of tigers in the wild, and to conserve the beauty of Yosemite Valley, regardless of human use. But accepting this should not preclude accepting arguments for conservation that are based on utilitarian value, particularly when we consider different levels of biological organization. For instance, populations of species provide vital ecosystem services such as pollination, such that loss of a population can cause loss of an ecosystem service that has utilitarian value. If the continued existence of populations of the species elsewhere means that the species itself is not threatened, or if the population lives in a human-dominated, non-wild landscape, then arguments for the intrinsic value of species and ecosystems are inadequate. Given that population declines are perhaps the most prevalent aspect of biodiversity loss [14], failure to recognize the utilitarian value of populations does a disservice to conservation.

Viewing reasons for conserving nature at different levels of biological organization thus clarifies when alternative arguments are most relevant, in particular that arguments based on intrinsic value are most commonly associated with species and ecosystem levels. This takes us some way toward melding utilitarian and intrinsic reasons for conservation, enabling both to be included within a multifaceted approach.

The article also wades into the debate on monetization.

I agree with using all the tools. We also have to recognize that even reasonable people have a range of values, and there are also unreasonable people out there, and we have to find arguments that appeal to a critical mass of people in order to make any progress.

The Windup Girl

Another book I’m reading (actually listening to) right now is the The Windup Girl by Paolo Bacigalupi. This is biopunk, possibly my favorite genre when it is done well. I won’t spoil the plot below, but I’ll tell you some of the background on what is going on in the society about halfway through the book, so if you prefer to read it and discover this gradually, then stop reading now!

The interesting thing about this society (Southeast Asia, supposedly about 100 years in the future), is that it has very advanced scientific and technological knowledge compared to our current society, and yet it is extremely energy and resource poor compared to our current society. All food seems to be genetically engineered by a few western companies (“calorie companies”). At some point there has been a catastrophic loss of biodiversity. At the point in the book where I am now, there are hints that these companies themselves have engineered the pests and diseases that brought this about. We don’t know why – maybe as a form of competition to attack each others products, or maybe to attack non-genetically engineered organisms. Whatever the original strategy, these plagues have devastated natural ecosystems and come back to attack the company crops themselves, and also to sometimes jump to humans, so that everyone is sick and starving and the companies are trying to hunt down any surviving stashes of biodiversity.

The society is also extremely energy poor. Climate change and sea level rise have been devastating, and fossil fuels seem to be entirely gone with the exception of coal, the latter rare and used only by the government for pumping in a last-ditch effort to keep the ocean at bay. There is some methane available from digesting animal manure, again tightly controlled by the government. For mobile power, they wind “springs” using animal power, including “megadonts” which sound like reconstituted mammoths. I have a couple questions on plausibility here, neither of which detracts from the story which I am really enjoying. First, which such advanced biological technology developed over 100 years, it is surprising not to see solar power, wind power, fuel cells, or even nuclear power. In fact, there seems to be no form of electricity at all. Second, I imagine mammoths would eat a lot. Let’s say you grow food, feed the mammoths, have them wind the springs, then digest their manure to obtain methane all very efficiently. I find it hard to believe that if you took whatever you are feeding the mammoths and digested it directly, you would not obtain more energy. The exception might be if the mammoths go foraging themselves and eat something that grows naturally on land that will not grow anything else, and that particular plant is digestible by mammoths but not by methane-generating bacteria. With a very limited range of plants available, maybe this is not all that implausible in the bizarre universe of this book.

the case of the missing mammals

Where would the large mammals be if humans hadn’t come along?

How would the world look if humans had never spread out across the Earth? For a start, we’d have a lot more forest, much less pollution, and the stars would look unbelievably bright. But, as a new map shows, the planet would also be absolutely teeming with large mammals, from the Serengeti to Northern Europe and all the way across the Americas. Researchers at Denmark’s Aarhus University have created a global map which shows the distribution of large mammals as it may have been if humans had never left Africa…

The Americas used to be home to 105 large mammal species, including sabre-toothed cats, mastodons, giant sloths and giant armadillos, which all disappeared in the last 100,000 years or so. A previous study by the Aarhus University research team showed that human activity was responsible for this mass extinction

“The reason that many safaris target Africa is… that it’s one of the only places where human activities have not yet wiped out most of the large animals,” said Postdoctoral Fellow Søren Faurby, lead author on the study.

The highest levels of diversity would be in central regions of north and south America, especially parts of Texas, the U.S. Great plains and regions of Brazil and Argentina.