by Playfuls Staff |
6th October 2006
U.S. scientists say they've determined how an organism's environmental temperature affects the size and [more] weight of its offspring.
Michael Angilletta of Indiana State University, Chris Oufiero of the University of California-Riverside, and Adam Leaché of the University of California-Berkeley used a new statistical approach that can test multiple theories at the same time -- an approach they hope will shed light on many evolutionary questions.
Previous research revealed lizards in colder environments produce larger offspring than lizards in warmer environments.
So why do animals in colder climates produce larger offspring? One theory suggests the larger size counteracts their slow growth in colder conditions. Another theory suggests large offspring come from large mothers, who grow large because they require more energy to reproduce in the cold.
When they tested the theories with their new approach, the team concluded temperature's effect on reproduction is a byproduct of its effect on adult size.
"This result could have widespread significance," said Angilletta. "Temperature determines the adult size of virtually all organisms. For many of these organisms, we expect temperature to also leave an imprint on reproduction."
The research appears in the journal The American Naturalist.
© 2006 UPI
