[CINC] Scientists question "the island rule"

[Mary_C_Fritzsche at nps.gov]

Thanks so much, David, for sending this out to all of us, and I'm posting
Kate Faulkner's response so that folks can look for the paper by Ted Case
if interested.

         Thanks for this very interesting article.

         I had never heard of an "optimal body size" rule that is specific
         to animals on islands.  I think the paper was using islands to
         test the OBS rule and that this rule doesn't have an special
         relationship to islands.

         The "island rule" that I am aware of is that small animals tend to
         become larger on islands (like the Island Scrub Jay) and large
         animals become smaller (pygmy mammoth and island fox).

         I believe that animals around the size of a rat are the dividing
         line between "big" and "small" animals.

         I have a copy of a paper on island body size.  However, it is too
         big to e-mail.  It was written by Ted Case and is in the 1978
         journal Ecology.

         Kate

         Kate Faulkner
         Chief, Natural Resources Management
         Channel Islands National Park
         1901 Spinnaker Drive
         Ventura, CA 93001
         805-658-5709 (office)
         805-804-0044 (cell)
         805-658-5799 (fax)
         kate_faulkner at nps.gov

Clare Fritzsche
Volunteer Coordinator Assistant
Channel Islands National Park
1901 Spinnaker Drive
Ventura, CA 93001
(805) 658-5733
FAX: (805) 658-5799
Mary_C_Fritzsche at nps.gov



  (I tried to send this several days ago but I don't think it came
through.)

http://www.tau.ac.il/lifesci/departments/zoology/members/meiri/documents/Raiaetal2010onesizedoesnotfitall.pdf


In this article (One size does not fit all: no evidence for an optimal
body size on islands) found at the above link, scientists claim to have
found evidence to refute the island rule, a theory that states species
that do not face competition will evolve towards a standard optimum body
size. The scientists use evidence to show this does not actually happen
on islands.

Although we have heard reasons for species on the Channel Islands
evolving to be smaller or larger, I have never heard it attributed to
this idea of evolving towards a standard optimal size. I did not see the
island fox, island scrub-jay, or pygmy mammoth listed in this study.

David Chubb