[Taxacom] flattened primate nails and early feathers (and teleology)

Kenneth Kinman kinman at hotmail.com
Fri Jan 12 09:53:09 CST 2018


Dear All,

      With regard to my P.S., I don't see how using the phrase "drove the evolutionary transition" is all that teleological.  If I had suggested that claws evolved into flattened nails to achieve a goal (in order to become a better grasper of tree limbs), that would be teleological, although not nearly as blatant as babies shaped like footballs.

       Some researchers had proposed that flattened nails evolved along with increasing body size, but the discovery in 2011 of such nails in tiny fossil 6-inch primates (genus Teilhardina) seems to show such flattening preceded increases in body size.  It is similar to the discovery that the function of feathers initially involved something other than flight.  Whether that initial function was for insulation or display or something else is still being debated.

       I still believe that early feathers could have begun on dinosaur tails (sort of like those found in later, E. Cretaceous fossils of Psittacosaurus).  A display function could have been slowly exapted into insulatory functions as they spread to the rump (insulation to help keep eggs warm) and then body insulation in general.  Notice that I use the word exapted (not pre-adapted, which some might regard as teleological).  Anyway, the initial display function could have been a sexual display, but I still think an even earlier display function could have served a sort of predator evasion function (either confusing the predator or at least attracting it to a less vital part of the body, the tail).  Just imagine a small Kentrosaurus-like dinosaur (tiny head), but instead of spines on the tail, just a bunch of proto-feathers (at the end of the tail) that looks more like a head than the actual head does.

Kentrosaurus: https://en.wikipedia.org/wiki/Kentrosaurus#/media/File:Kentrosaurus_NT.jpg

                        -------------------Ken

________________________________
From: John Grehan <calabar.john at gmail.com>
Sent: Wednesday, January 10, 2018 8:45 PM
To: Kenneth Kinman
Cc: taxacom at mailman.nhm.ku.edu
Subject: Re: [Taxacom] human eyes & ectoparasites

When Ken says "but it is not clear what actually drove the evolutionary transition from claws to nails.  It could be something involved in grasping and locomotion in trees." the real question is whether anything 'dives' a particular transition. Again the appeal and mysticism of teleology is once again evident and it is what keeps evolution outside science.

John Grehan

[https://ipmcdn.avast.com/images/icons/icon-envelope-tick-round-orange-animated-no-repeat-v1.gif]<https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=icon>    Virus-free. www.avast.com<https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=link>

On Wed, Jan 10, 2018 at 9:07 PM, Kenneth Kinman <kinman at hotmail.com<mailto:kinman at hotmail.com>> wrote:
Hi Derek,

       I see that Furtive Fauna was published over 20 years ago.  I suspect the reason you have never run across that hypothesis before is that it probably didn't have much going for it and it just faded away.  Having good near-vision probably came first, and that later enabled them to become better ectoparasite groomers (not the other way around).  It's a bit like saying birds developed feathers in order to fly, but we now know feathers probably first evolved for insulation (although I have suggested a possible even earlier advantage of feathers if they first evolved on the tail and that  may have helped bird's dinosaur ancestors in predator evasion, i.e. please attack my attractive but expendable tail, rather than my head).

       And I can't see any "obvious consequences" for the origin of written language or civilization.  I don't think there was anything particularly tiny about the earliest written words, numbers or characters.  Not nearly as tiny as lice or fleas.

               ----------------Ken

P.S.  Having flattened nails (instead of claws like other mammals) seems to also make primates better ectoparasite groomers, but it is not clear what actually drove the evolutionary transition from claws to nails.  It could be something involved in grasping and locomotion in trees.

________________________________
From: Taxacom <taxacom-bounces at mailman.nhm.ku.edu<mailto:taxacom-bounces at mailman.nhm.ku.edu>> on behalf of Derek Sikes <dssikes at alaska.edu<mailto:dssikes at alaska.edu>>
Sent: Wednesday, January 10, 2018 11:22 AM
To: taxacom at mailman.nhm.ku.edu<mailto:taxacom at mailman.nhm.ku.edu>
Subject: [Taxacom] human eyes & ectoparasites

All,

I was just reading Roger Knutson's 'Furtive Fauna' in which was an
interesting hypothesis I hadn't come across before and wonder if anyone
knows more about it.

Our ability to see small things close up (such as text) resulted from
generations of ectoparasite grooming. Had our distant ape ancestors not had
to deal with ectoparasites our eyes might not be very good at near-vision
(with obvious consequences for the origin of written language and rise of
civilization).

Knutson stated it factually, but the book has no in-text citations and it's
not clear where he got the idea.

I don't know much about the near-vision ability of vertebrates to know how
likely this hypothesis is. Do non-grooming mammals have poor near-vision?

I'm always looking for ways to explain to entomology students how the world
might be different if arthropods hadn't dominated it, and this might be
another example.

Interested to hear other's thoughts on this.

Thanks,
Derek


--

+++++++++++++++++++++++++++++++++++
Derek S. Sikes, Curator of Insects
Associate Professor of Entomology
University of Alaska Museum
1962 Yukon Drive
Fairbanks, AK   99775-6960

dssikes at alaska.edu<mailto:dssikes at alaska.edu>

phone: 907-474-6278<tel:907-474-6278>
FAX: 907-474-5469<tel:907-474-5469>

University of Alaska Museum  -  search 395,696 digitized arthropod records
http://arctos.database.museum/uam_ento_all
<http://www.uaf.edu/museum/collections/ento/>
Entomology | Museum<http://www.uaf.edu/museum/collections/ento/>
www.uaf.edu<http://www.uaf.edu>
Overview Welcome to the University of Alaska Museum Insect Collection. The collection was established as part of a NSF - funded Arctic Archival Observatory grant in ...



+++++++++++++++++++++++++++++++++++

Interested in Alaskan Entomology? Join the Alaska Entomological
Society and / or sign up for the email listserv "Alaska Entomological
Network" at
http://www.akentsoc.org/contact_us <http://www.akentsoc.org/contact.php>
[https://s0.wp.com/i/blank.jpg]<http://www.akentsoc.org/contact_us>

Contact | Alaska Entomological Society<http://www.akentsoc.org/contact_us>
www.akentsoc.org<http://www.akentsoc.org>
Alaska Entomology Network. Currently, the best way to get in touch with the entomological community in Alaska is to subscribe to the Alaska Entomology Network e-mail ...



_______________________________________________
Taxacom Mailing List
Taxacom at mailman.nhm.ku.edu<mailto:Taxacom at mailman.nhm.ku.edu>,
http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
Taxacom Info Page - mailman.nhm.ku.edu<http://mailman.nhm.ku.edu> Mailing Lists<http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom>
mailman.nhm.ku.edu<http://mailman.nhm.ku.edu>
Taxacom is an e-mail list for biological systematics. Named and brought to life by Drs. Richard Zander and Patricia Eckel, Taxacom began its peripatetic existence on ...



The Taxacom Archive back to 1992 may be searched at: http://taxacom.markmail.org
[http://taxacom.markmail.org/images/ml-logo.png]<http://taxacom.markmail.org/>

Taxacom Home - MarkMail - Community libraries<http://taxacom.markmail.org/>
taxacom.markmail.org<http://taxacom.markmail.org>
MarkMail is developed and hosted by MarkLogic Corporation. MarkMail is a free service for searching mailing list archives, with huge advantages over traditional ...




Send Taxacom mailing list submissions to taxacom at mailman.nhm.ku.edu<mailto:taxacom at mailman.nhm.ku.edu>
To subscribe or unsubscribe via the Web, visit: http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
Taxacom Info Page - mailman.nhm.ku.edu<http://mailman.nhm.ku.edu> Mailing Lists<http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom>
mailman.nhm.ku.edu<http://mailman.nhm.ku.edu>
Taxacom is an e-mail list for biological systematics. Named and brought to life by Drs. Richard Zander and Patricia Eckel, Taxacom began its peripatetic existence on ...



You can reach the person managing the list at: taxacom-owner at mailman.nhm.ku.edu<mailto:taxacom-owner at mailman.nhm.ku.edu>

Nurturing Nuance while Assaulting Ambiguity for 31 Some Years, 1987-2018.
_______________________________________________
Taxacom Mailing List
Taxacom at mailman.nhm.ku.edu<mailto:Taxacom at mailman.nhm.ku.edu>,
http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
The Taxacom Archive back to 1992 may be searched at: http://taxacom.markmail.org

Send Taxacom mailing list submissions to taxacom at mailman.nhm.ku.edu<mailto:taxacom at mailman.nhm.ku.edu>
To subscribe or unsubscribe via the Web, visit: http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
You can reach the person managing the list at: taxacom-owner at mailman.nhm.ku.edu<mailto:taxacom-owner at mailman.nhm.ku.edu>

Nurturing Nuance while Assaulting Ambiguity for 31 Some Years, 1987-2018.



More information about the Taxacom mailing list