Comments on: Do new discoveries ever “rewrite evolutionary history”?

By: Darren Naish

Darren Naish — Thu, 02 Sep 2010 13:22:24 +0000

I think that claims that dinosaur phylogenies differ radically from one another, or that they vary much between workers, are overblown, and major areas of consensus have long (or always) been apparent, even for supposedly controversial sauropods. The existence of what we might regard as two ‘opposing schools’ in the study of sauropod phylogeny create the impression that phylogenies have been radically different, but in recent years the two ‘schools’ have been converging in the larger picture and most sauropod phylogenies recover the same basic topology.

I also strongly agree with the fact that comparing dinosaurs and catarrhines is a red herring: sauropod phylogeny might look ‘unstable’ because (until the late 1990s) titanosaurs were regarded by school 1 as closer to diplodocoids than to brachiosaurs (as recovered by school 2)… but if we analyse the history of total primate phylogeny, we see similar problem areas: tarsiers jump on and off the anthropoid branch, for example, and the possible paraphyly of groups like adapiforms and omomyiforms would create for messy ‘competing’ phylogenies.

Re: comment 1 above – condors/New World vultures are best regarded as close to other raptors after all; the idea that they were close to storks was short-lived and based on a dodgy interpretation of genetic data.

By: amphiox

amphiox — Thu, 02 Sep 2010 07:39:05 +0000

It seems to me that the two groups might have been chosen because they are the two groups in which new discoveries are most likely to be reported in the popular media as “rewriting evolutionary history”. Since catarrhines is the group that includes human ancestry and it seems that every. single. fossil. bone. ever. found. will always, invariably be said to “rewrite the evolutionary history” of humans (and so far, generally, never does). And dinosaurs, of course, are the prehistoric group that gets the most press in general.

By: Nathan Myers

Nathan Myers — Wed, 01 Sep 2010 18:28:51 +0000

I’m stumping for “flabbergasted” and “gobsmacked”.

By: Ed Yong

Ed Yong — Wed, 01 Sep 2010 15:54:08 +0000

@ Rhacodactylus – A quick search of the archives shows that I have used the word “cautious” in 11 posts and “caution” in 22. I have used “rewritten” twice, once in this post and once about memories. I have used the word “baffled” twice: in one instance, the creature that was baffled was a clownfish and in the other, it was me!

;-p

By: Brian Switek

Brian Switek — Wed, 01 Sep 2010 15:22:27 +0000

Thanks for including me in this post, Ed. (And I love the top illustration, by the way. Brilliant.)

Just one note that I did not fully explain in my e-mail; Ramapithecus is no longer a valid genus. As it turned out, the fossils which were originally called Ramapithecus really belonged to a genus of orangutan-like fossil ape from the Siwalik Hills of India and Pakistan called Sivapithecus. It was the recognition that Ramapithecus = Sivapithecus that played a major role in removing it from its place as a potential hominin ancestor.

http://en.wikipedia.org/wiki/Sivapithecus

By: Rhacodactylus

Rhacodactylus — Wed, 01 Sep 2010 14:33:25 +0000

I love the way science writing is approached, scientists are never “cautiously optimistic,” or “curious but with doubts,” or “interested in a new and exciting discovery,” No, scientists only ever experience moments of being “baffled” or having their whole worlds “re-written.” It must be fun being a scientists, only ever experiencing total swings of emotion with absolutely no middle ground.

By: Walter S. Andriuzzi

Walter S. Andriuzzi — Wed, 01 Sep 2010 13:54:24 +0000

(Of course I am still waiting for “fossil rabbits in the Precambrian” XD)

By: Walter S. Andriuzzi

Walter S. Andriuzzi — Wed, 01 Sep 2010 13:23:05 +0000

“[...] researchers should try to assess how mature and stable their data are before making bold claims about the evolutionary history of any particular group”. He is right, but I think that usually the hype is due to the press, rather than the researcher themselves.
Personally right now I can think of just three relatively recent discoveries (or groups of discoveries) which rewrote evolutionary history as I knew it:
- condors being Ciconiiformes rather than vultures
- Annelida being closer to Mollusca than to Arthropoda (I learned this just a year ago reading Dawkins’ “The Ancestor’s Tale”, and after five years of university it was totally unexpected… the definite proof I was waiting for that the professor of animal systematics in my ex-university should really update. Or retire)
- protists being a polyphyletic group made of several kingdoms
But I am sure there are many others