What is living fossil ?

Question

What is living fossil ?

Answer 1

John McCain?

Answer 2

Rupert Murdoch?

Answer 3

Living fossils are metaphorically speaking animals that retain features which, in terms of their group, can be sensibly seen as primitive.  For mammals, for example, the platypus has old-fashioned features.  It reproduces by laying eggs.  That one trait that qualifies it for the honour of sometimes being termed a living fossil.

It doesn't mean the whole animal must be somehow 'old fashioned' or 'little changed' over long stretches of time.  The platy also has remarkably derived features. such as a mass of electro-sensors built into its beak for detecting electrical impulses generated by the movement of prey animals in water.

Answer 4

A living fossil is a creature whose type has changed so little

that it is comparable with fossilized specimens.

The horse shoe crab is an example.