African phororhachoid "terror bird" from Eocene

[bh480@scn.org]

From: Ben Creisler
bh480@scn.org

Not Mesozoic, but of possible interest to the DML:

Cécile Mourer-Chauviré, Rodolphe Tabuce, M?hammed 
Mahboubi, Mohammed Adaci and Mustapha Bensalah (2011)
A Phororhacoid bird from the Eocene of Africa. 
Naturwissenschaften  (advance online publication)
DOI: 10.1007/s00114-011-0829-5
http://www.springerlink.com/content/2p102j3676418901/


The bird fossil record is globally scarce in Africa. The 
early Tertiary evolution of terrestrial birds is 
virtually unknown in that continent. Here, we report on a 
femur of a large terrestrial new genus discovered from 
the early or early middle Eocene (between ~52 and 46 Ma) 
of south-western Algeria. This femur shows all the 
morphological features of the Phororhacoidea, the so-
called Terror Birds. Most of the phororhacoids were 
indeed large, or even gigantic, flightless predators or 
scavengers with no close modern analogs. It is likely 
that this extinct group originated in South America, 
where they are known from the late Paleocene to the late 
Pleistocene (~59 to 0.01 Ma). The presence of a 
phororhacoid bird in Africa cannot be explained by a 
vicariant mechanism because these birds first appeared in 
South America well after the onset of the mid-Cretaceous 
Gondwana break up (~100 million years old). Here, we 
propose two hypotheses to account for this occurrence, 
either an early dispersal of small members of this group, 
which were still able of a limited flight, or a 
transoceanic migration of flightless birds from South 
America to Africa during the Paleocene or earliest 
Eocene. Paleogeographic reconstructions of the South 
Atlantic Ocean suggest the existence of several islands 
of considerable size between South America and Africa 
during the early Tertiary, which could have helped a 
transatlantic dispersal of phororhacoids.