13-03-2017
A new research with 152 million year old fossil egg discovered on the rocks of the Upper Jurassic on the coastal cliffs of western Portugal shows that these eggs are from relatives of crocodiles and that their type of egg has changed very little since then.
The eggs were found on rocks with about 152 million years, making them the oldest fossil eggs of crocodilomorphs known to date - the ancestor group common to all crocodiles.
One of the most striking aspects of these eggs is their resemblance to today's crocodiles, indicating that the evolution of this egg morphology has been very slow and has changed very little in the last 152 million years of history of crocodiles and their ancestors. There is a certain degree of variation between eggs, for example, in size or in microscopic changes in the egg shell, but the fundamental morphological characteristics are the same.
The eggs were considered slightly different from any other eggs previously described; two new egg species were considered to be equivalent to new species (but only applied to eggs).
