Which of the following statements about the cladogram of animals is true? a) backbones evolved before segmentation. b) radial symmetry appears only once in the cladogram. c) segmentation evolved more than once in different branches of the cladogram. d) all deuterostomes have bilateral symmetry and cephalization.

The correct option is c. Segmentation evolved more than once in different branches of the cladogram.

Phylogenetic studies help to identify and understand evolutionary relationship between different life forms. It uses a diagram called as Cladogram to represent the branching of the evolutionary relationships. In cladogram studies each branching point tells a fundamental character of the evolutionary significance. Cladogenesis separates the gene pool by splitting into two or more than two separate pools each of which gives rise to one or more new species. Segmentation implies repeated parts and many animals consist of such repeated parts. Therefore, segmentation appears more than once in different cladogram branches.

spiders belong to a group of arachnids.

arachnids have the following traits :

they have two body parts.

they have eight legs unlike insects which have 6 legs.

they have no wings.

these traits distinguish them from insects.

the information that antonio is doubting us the statement that spiders differences are as a result of being first to evolve.

this is because the evolution of one species is independent of the other species.