During the century following the publication of Darwin's (24) Origin of Species, biological
taxonomy waited for the revolution that should have followed upon acceptance of an …

Elements of the vertebrate skeleton are initiated as cell condensations, collectively termed
the 'membranous skeleton'whether cartilages or bones by Grüneberg (1963) …

Homology—a similar trait shared by different species and derived from common ancestry,
such as a seal's fin and a bird's wing—is one of the most fundamental yet challenging …

Explaining altruistic cooperation is one of the greatest challenges for evolutionary biology,,.
One solution to this problem is if costly cooperative behaviours are directed towards …

Vertebrate Hoxd genes are sequentially activated during the morphogenesis and pattern
formation of the limb. Using the approach of gene disruption via homologous recombination …

NEW specimens of the earliest known tetrapod limbs shows them to be polydactylous. The
forelimb of Acanthostega has eight digits and the hindlimb of Ichthyostega has seven. Both …

This work serves as a compendium of anatomical resources upon which a companion
phylogenetic analysis of Aves and related Theropoda (Avialae) was based. Following a brief …

A comprehensive analysis of amniote interrelationships is presented in an attempt to test
turtle interrelationships. The results refute earlier hypotheses that turtles are related to …

Patterns of ossification are described in the endo-and exoskeleton of Alligator
mississippiensis. The occurrence of a dermo-supraoccipital is discussed in light of the …

Persistent contradictions in well supported empirical findings usually point to important
scientific problems and may even lead to exciting new insights. One of the most enduring …