User:Justin Wabscott/sandbox

Vernix caseosa

A repeated complaint against the Aquatic Ape Hypothesis was that it made no predictions. In 'The Descent of the Child' (1994) Elaine Morgan noted that, "Almost every human baby comes into the world smeared like a long-distance swimmer with a layer of grease. ... known to scientists as the Vernix caseosa, which is Latin for 'cheesy varnish'". In 2005, the BBC Radio 4 series "Scars of Evolution", presented by Sir David Attenborough, proposed a testable hypothesis: "If vernix, as suggested by Elaine Morgan, is an adaptation to entering the water at birth or immediately after, then it will not be unique to humans, as extensively reported in the scientific literature , but will also be found in other animals that enter the water soon after being born."

The first suggestion that vernix might not be unique to humans came from Don Bowen at Dalhousie University, who observed that newborn Harbour Seals have a greasy coating, and unlike other seal species, enter the water soon after birth. In 2016 Tom Brenna at Cornell University, with the help of Judy St Leger at San Diego Seaworld, obtained samples of a vernix-like substance on California sealion pups and established that its molecular composition is comparable to human vernix, being rich in both branch chain fatty acids (BCFAs) and squalene. .

Brenna's data are the first to demonstrate the production of true vernix caseosa in a species other than Homo sapiens. Its presence in a marine mammal supports the hypothesis of an aquatic habituation period in the evolution of modern humans.