The good news is that the "everything is going extinct" meme is wrong. Yes, a lot of animals are endangered, but very few actually go extinct and, thanks to cross-breeding, migration and genetic manipulation, more species are being made today than are being pushed over the edge.
ALL OF THESE scientists agree that human-driven extinction is a crisis. They are not allied with reactionary politicians or climate-change skeptics, and they are all committed to the flourishing of the natural world. But the vitriol of the extinction debate makes clear they see more than statistics at stake.
“If you express a view that’s different to some people, they say you’re anticonservation, and that’s not true,” said Nigel Stork, a conservation biologist at Griffith University in Australia and the author of a 2013 paper published in the journal Science that argued the extinction rate was not as bad as had been previously feared. “Conservation is working. There have been fewer extinctions because we’ve been conserving a key part of the world.”
In 1979, Berkeley ecologist Norman Myers published a book called “The Sinking Ark,” which claimed 40,000 species were disappearing each year. The next decade, a biologist who worked for the World Wildlife Fund predicted up to 20 percent of all species would disappear by the turn of the millennium. That didn’t happen, but the drumbeat of alarms continues: A much-publicized paper in 2004 warned that by 2050, climate change could put 1 million species at risk of extinction.
There’s at least one problem with these predictions: Where are the bodies? Actual documented extinctions are vanishingly rare. “If you ask any member of the public to name 10 species that have gone extinct in the last century, most would really really struggle,” Ladle said. “Then you’ve got the world’s most famous conservationists telling you that 27,000 are going extinct every year. The two don’t tally up.” The International Union for Conservation of Nature, which keeps the most definitive list of extinct and threatened species, has counted just over 800 total confirmed animal extinctions since the year 1600....
...[W]hen scientists talk about thousands of species going extinct in a year, they aren’t counting disappearances: They’re making extrapolations based on estimates of habitat loss, and of how many species currently exist, and how many have existed in history.
The new species and types being created have enormous benefits for man, and the world, as we boost farm productivity which allows more land to be returned to nature.
The problem with this argument is that named apples are being compared to un-named oranges. For an extinction to have been documented the existence of the species must have been known, and it will have been given a name. The IUCN extinct and extinct in the wild categories are filled, by definition, only with named species.
ReplyDeleteMost of the species in the modern world still do not have names - they can disappear without us formally knowing that they ever existed and thus never appear on a list of extinctions.
The much higher estimates of total extinction rates are based - as the extract states - on extrapolations from rate of habitat loss and species density per unit area. Like all estimates and forecasts these are subject to error, but I doubt that anyone can seriously argue that the true rate of extinctions can be calculated by only counting named species.
The "ask the public to name 10 species...." argument is about as shakey as arguments get. How many of the public can name the top ten causes of human mortality ?, does that mean that people are not going to die from those causes ?
Agreed, a lot of conservationists are professional pessimists, mostly for good reasons.
The extrapolation work is all crap and was done by people who admit it is all crap and that it was designed to achieve a political purpose.
ReplyDeleteSee >> http://terriermandotcom.blogspot.com/2013/01/extinction-of-fantasy-numbers-about.html
"Here's the essential question: Do you base your extinction rate on observation of the entire world for 500 years, or do you base it on a mathematical extrapolation of the entire world based on a two acre sample of life collected from a single Caribbean mangrove swamp island on a single day?"
Most species have, in fact, been named, and the number of larger new species now being discovered is very low and they tend to be in very remote areas largely not impacted by man (deep ocean) or are insects that are very difficult to eradicate.
The IUCN list, is, quite frankly, very comprehensive and for at least the last 20 years it has reported on more species being RE-discovered "after extinction" than being pushed into extinction.
Stork's paper is perhaps the best single-paper review of the literature. http://www.griffith.edu.au/__data/assets/pdf_file/0009/351729/Stork-Biod-Cons-2009.pdf
ReplyDeleteSee the section entitled: "Why predicted extinction rates do not match empirical data"
He write: "So what can we conclude about extinction rates? First, less than 1% of all organisms are recorded to have become extinct in the last few centuries and there are almost no empirical data to support estimates of current extinctions of 100 or even one species a day.
"Second,the most frequently used predictions for global extinction rates are still largely based on the
species–area relationship and the fact that large areas of forests (in particular) are being converted. As Lewis (2006) suggested these and the first models of the impacts of climate change on biodiversity, are first passes with subsequent more sophisticated analyses frequently
reducing first estimates of extinction rates....
"Third, the evidence is so overwhelming
that extinction threats vary for different groups of organisms and different faunas and floras that it is surprising that there are still some who seek to draw conclusions on global extinction rates for all organisms based on the knowledge of just a few very highly threatened groups."
Or just look at the US. We have plowed, shot, paved, drained, constructed, poisoned, pumped, planted, burned, cut and netted most of the country. Not too many species pushed into extinction for all that. Half of those that are normally named never existed at all, or still exist. And so it goes, around the world outside of small Pacific Island endemics (mostly birds killed by rats, cats and mongoose).
There's a bit of a chicken and egg problem here; to quote Nigel Stork from https://theconversation.com/we-can-name-all-of-earths-species-but-we-may-have-to-hurry-11815; "But we believe that there is good evidence that contemporary extinctions are not as high as many had thought. We contend that this is for several reasons, including the fact that conservation efforts to protect the world’s biodiversity hotspots has been very effective to date."
ReplyDeleteSo conservation efforts based on concerns about rapid extinctions have slowed the rate of extinctions - does that really mean that we can stop worrying now ? Not while the human population continues to expand at current rates I would suggest.
He also says; "We contend that extinction rates are probably less than 5% per decade." Going with his 5 million eukaryote species, that 0.5 % per year is 25000 species extinctions per year. In a simplistic linear extrapolation which will never come true, but which starkly highlights just how steep that decline is, it means that every species on Earth will be extinct in 200 years.
The exact numbers are not important - what is important is that measures need to be taken to protect habitats and populations. All the species of rhinos, all species of elephants, all species of pangolins, just to give examples, are doomed to extinction unless they are protected against commercial exploitation. Their value per individual rises as they get scarcer, the value of stockpiled rhino horn will rocket on the day that the last rhino is killed, and the horn speculators know that very well. To borrow a well known phrase; the price of slowed extinctions is eternal vigilance.
No one is saying "stop worrying."
ReplyDeleteWhat is being said is "stop lying."
Very different things.
The simple truth is that "20,000 species a year are disappearing" line is a LIE and always has been.
Yes, species loss has slows from ONE a year to LESS than one a year. That's good news, and we want more of it.
But that good news has nothing to do with the lie that 20,000 species a year are disappearing (they aren't) nor does it move us forward in the protection of habitat, reduction in population growth rates, connection of corridors, slowing of over-fishing and deforestation.
"Sound science" is not just something we should be demanding from the "other" side, but ours as well.
Nuke Asia and you'd halt the elephant, rhino, tiger, shark, bear, ocean fish, and hundreds of other extinctions. Short of that an African/Asian recolonization project might work- or finally some kind of economic voodoo which prevented Asian countries from having wealthy elites...not very PC I know...
ReplyDeleteEducation first! And viagra, which I'm sure works much better than rhino horn.
ReplyDelete