Question

Explain how the bone patterns in mammalian limbs came about, using the theory of evolution from a common ancestor

Answer 1

Limbs are homologous construction which are serially repetitive. The ensuing hind limb was created by the old duplication incidents, the anatomical construction of the pectoral appendages including the genetic design has been duplicated by the ensuing hind limb which is control of the progress of induction, working together and ddevelopment. This complementary base of the limbs has important significance for its evolution.

Quantitative genetics theory is of the notion that genetic forecast has made limbs to undergo evolution in parallel solely among the stylopod, zeugopod and autopod which are corresponding segments.This genetic intake, observed in markings of phenotypic sheathing influence the variation that is relevant to draft coupled with the total immovability of limbs.

The entire phyla amphibians, reptiles, birds and mammals are known to be pentadactyl. The availability of pentadactyl limb indicates the inheritance of the specific trait from a single ancestor with continious modifications in the period of evolution.

Answer 2

The bone patterns in mammalian limbs can be further traced to the bone structure of the Xenarthra species as far as its histology is concerned. There has been a bone compactness showing pattern most specifically in the femur area between the species of Cingulata and Pilosa.