David Middleton thinks he's hit gold at Australia's ABC (archived here). What he's hit is amber. He should have heeded the warning. David wrote about an article that describes how a team of scientists, led by Dr Emma Sherratt of UNE, looked at lizards fossilised in amber, from the Caribbean.
|Amber means "stop" |
An unresolved question in ecology is whether the structure of ecological communities can be stable over very long timescales. Here we describe a wealth of new amber fossils for an ancient radiation of Hispaniolan lizards that, until now, has had a very poor fossil record. These fossils provide an important and previously unavailable perspective on an ecologically well-studied group and indicate that anole lizard communities occurring on Hispaniola 20 Mya were made up of the same types of habitat specialists present in this group today. These data indicate that the ecological processes important in extant anole communities have been operative over long periods of time.
This video is from Emma Sherratt, showing her amber-fossilized lizards - beautiful. Something you won't see at WUWT:
From the ABC article:
A community of lizards from the Caribbean, preserved for 20 million years in amber, have been found to be identical to their modern cousins, say researchers.
This suggests the different niches inhabited by the lizards have - incredibly - changed little over the past 20 million-year, report the team, in this week's Proceedings of the National Academy of Sciences.
"These fossils were really surprising because of how much detail they contained, allowing us to see how these lizards would have looked in real life," says the study's lead author Dr Emma Sherratt of the University of New England in Australia.Sherratt says it is "very striking" that the lizards don't seem to have changed at all during this long period, during, over which all the main animal types evolved....
..."Evidence of anolis lizards living unchanged in different niches for 20 million years, indicates these niches have been stable for that period of time," she says.
"That's quite surprising because these lizards have gone to other islands and over to the Florida mainland where they seem to evolve very rapidly. So it's not that they don't have the propensity to change, it's just that the structure of the environment has been stable enough that they haven't needed to change in 20 million years."
Hot vs cold, eggs vs live
Contrast Dr Emma Sherratt saying how evidence from the amber fossils suggests the ecological niches may have been unchanged over millions of years, with what David Middleton wrote:
I guess the Warmists are wrong about climate change endangering lizards……because 20 million years ago, the climate was warmer than today, and the lizards lived through at 3.0°C temperature spike 15 million years ago.
David compares this story about (warm climate) Caribbean anolis lizards to a different article about cold climate Liolaemus lizards. The contrast is striking. Evidence suggests the Caribbean lizards have not changed much. The Liolaemus lizards may be facing extinction with global warming, because they did change much. They changed from laying eggs to giving birth to live young. They adapted to cold climates and probably can't change back (my emphasis):
Researchers, including academics from the University of Exeter, investigated the hypothesis that historical invasions of cold climates by Liolaemus lizards – one of the most diverse groups of vertebrates on earth – have only been possible due to their evolution to viviparity (live birth) from oviparity (laying eggs). Remarkably, once these species evolve viviparity, the process is mostly irreversible and they remain restricted to colder climates.
The lizards that Emma Sherratt was researching were anolis lizards, which lay eggs. The article that David referred to as "wrong" was about how researchers think that cold climate lizards may become extinct because they no longer lay eggs!
Emma Sherratt was saying that the niches inhabited by these particular anolis lizards probably have changed little from what they were twenty million years ago. David Middleton was arguing that those niches had changed a lot, claiming that those same lizards "lived though at (sic) 3.0°C temperature spike 15 million years ago". His evidence is not from from the Caribbean, but from a chart that some un-named person drew, based on a paper in Science mag from 2001 (Zachos et al). David's diagram is not in the Zachos paper by the way, but I'm not saying it's wrong. I haven't checked. It looks as if it's derived from Figure 2 of the Zachos paper.
From the WUWT comments
July 28, 2015 at 3:47 pm
Ah but those are “special” lizards :)
July 28, 2015 at 3:49 pm
Lizards facing mass extinction…he’s saying they will migrate to the poles and then run out of poles…and go extinct
..right after they start growing bananas and coconuts in Quebec
References and further reading
Emma Sherratt, María del Rosario Castañeda, Russell J. Garwood, D. Luke Mahler, Thomas J. Sanger, Anthony Herrel, Kevin de Queiroz, and Jonathan B. Losos. "Amber fossils demonstrate deep-time stability of Caribbean lizard communities." PNAS July 27, 2015 doi: 10.1073/pnas.1506516112 (sub req'd)
- Ancient lizards in amber amaze scientists - by Stuart Gary at ABC Science
- Anoles Going Strong on Hispaniola Millions of Years Later - James Gorman at The New York Times
Pincheira‐Donoso, Daniel, Tom Tregenza, Matthew J. Witt, and Dave J. Hodgson. "The evolution of viviparity opens opportunities for lizard radiation but drives it into a climatic cul‐de‐sac." Global Ecology and Biogeography 22, no. 7 (2013): 857-867. DOI: 10.1111/geb.12052 (pdf here)
- Lizards facing mass extinction - press release from the University of Lincoln (UK)
Zachos, James, Mark Pagani, Lisa Sloan, Ellen Thomas, and Katharina Billups. "Trends, rhythms, and aberrations in global climate 65 Ma to present." Science 292, no. 5517 (2001): 686-693. DOI: 10.1126/science.1059412 (pdf here)
From the HotWhopper archives (David's a denier from way back)