Sexual size dimorphism (SSD) is highly prevalent in nature. Several hypotheses aim to explain its evolution including sexual selection, differential equilibrium and ecological niche divergence.

Macroevolution posed difficulties for Darwin and later theorists because species’ phenotypes frequently change abruptly, or experience long periods of stasis, both counter to the theory of incremental ...

One of the biggest questions in evolution is when and how major groups of animals first evolved. The rise of tetrapods (all limbed vertebrates) from their fish relatives marks one of the most ...