The similarity in the arrangement and structure exists mostly with the quads because we, just like cats, need to be able to flex and extend them so we need a lot of strength in them.
A fossil is the bone of a long dead animal that has been in the ground Harding for thousands to millions of years.
There are basically three types of evolution divergent, convergent and parallel evolution.
a) Divergent Evolution – As the name depicts the species in this form of evolution becomes divergent i.e they evolve to become different from each other. This form of evolution is responsible for the current diversity of organisms existing on planet earth. For example human and apes evolved from a common primate ancestor.
b) Convergent Evolution – In this evolution, different species of organisms living in a similar biosphere start share common traits in the form of analogous features. For example – Whale and fish are not closely related species but they both have fins which are different in structure but have the same function.
c) Parallel evolution – In this evolution the similar characteristics between the two set of organisms are maintained though the two species continue evolving separately. For example - marsupial mammals of Australia and the Placental mammals
