Bagaceratops evolved later but retains more primitive characteristics than its earlier relative.

Another primitive characteristic is the short symphysis of the mandible.

How could man as a species progress when there was greater survival value in retaining primitive characteristics?

Both families share a number of primitive characteristics.

This combination of modern and primitive characteristics seem to set the Atapuerca boy apart from any previously recognized species, the researchers said.

The marginal teeth were high-crowned, with only a few cusps, which is a primitive characteristic.

Because of its ancient ancestry and "primitive" characteristics, it has been described as a "living fossil".

Archostemata is an ancient lineage with a number of primitive characteristics.

Would it be such a surprise to find many of these primitive characteristics hidden in some deep remove of our psyches?

Because of this primitive characteristics, the genus was considered by some as not being true orchids.