Question

How reliable are morphological and molecular data in evolutionary studies? What are their weakness? How can they complement each other?

Answer 1

Ans: Evolutionary studies conducted on the basis of molecular data like DNA and amino acid sequences are considered more reliable than studies conducted on the basis of morphological characters. Morphological characters demonstrate a higher rate of convergent evolution than molecular data.

For example, some morphological characters arise for distantly related organisms through convergent evolution. Closely related species evolve simultaneously if situated in different parts of the world and thus, can give rise to 2 different species. But, while constructing a phylogenetic tree, those 2 initial species should be shown as close relatives.

* Some of the weaknesses of using morphological and molecular characters for evolutionary studies include-

1. The assay is time-consuming

2. Assy can't be performed for mixed samples

3. The morphological approach can't be applied for all cases

4. Mutations can't be detected

Ancestors also show similar morphological characters which have similar molecular sequences thus, complement each other.