Re: New Zealand's Giant Eagle Showed Rapid Size Gain ???

[Ronald Orenstein <ron.orenstein@rogers.com>]

At 06:04 PM 1/9/2005, DinoBoyGraphics@aol.com wrote:
> What is the fossil record like for the Australian mini-eagle?  Not to play 
> devils advocate, but couldn't the australian eagle have been undergoing a 
> size squeeze the last few million years?

I would consider this somewhat unlikely as the Little Eagle (Hieraeetus 
morphnoides) is within the range of the other species in the genus 
Hieraeetus.  From Ferguson-Lees and Christie, Raptors of the World (range 
includes both sexes):

Bonelli's Eagle H. fasciatus: 1.56-2.5 kg
African Hawk Eagle H. spilogaster: 1.15-1.75 kg
Wahlberg's Eagle H. wahlbergi: .437-1.4 kg
Booted Eagle H. pennatus: .840-1.25 kg
Little Eagle H. morphnoides: .440-1.25 kg
Ayres' Hawk Eagle H. ayresii: .685-1.05 kg

The authors, in fact, consider that the Little Eagle and the Booted Eagle 
form a superspecies.  Whether true or not, the Australian birds do not seem 
to represent a significant divergence (which suggests in turn that 
Harpagornis, if it is indeed closer to the Little Eagle than to other 
Hieraeetus spp (do the authors suggest this?) must have evolved giantism 
very rapidly.


--
Ronald I. Orenstein                           Phone: (905) 820-7886
International Wildlife Coalition              Fax/Modem: (905) 569-0116
1825 Shady Creek Court
Mississauga, Ontario, Canada L5L 3W2          mailto:ron.orenstein@rogers.com