Question

Match the following examples to the correct type of evolutionary evidence. Species that do not walk have remnants of pelvic and hip bones [Choose ] [Choose] There is only 1 amino acid difference between humans and chimps when making up the Cytochrome C protein used in the ETC of Cellular Respiration Anatomical evidence Fossil evidence Biochemical evidence Biogeographical evidence Archaeopteryx organism shows as an intermediate species between reptiles and birds Embryological evidence Marsupials are found mostly on the continent of Australia [Choose Humans and rabbits have gill slits during various stages of their development [Choose)

Answer 1

Many important evidences are present in our nature which show that evolution has indeed taken place on earth. These evidences clearly demonstrate that the various new life forms have evolved since the creation of life.

Species that do not walk have remnants of pelvic bone and hip bones $\rightarrow$ Anatomical evidence (Morphology refers to the external structure of an organism and anatomy refers to the internal structure and functional organisation. The study of characteristics of diverse range of living organisms is used as evidence for the evolution. By comparing the morphology and anatomy, the similarities as well as differences between the present living and remote extinct organisms can be known. As for example, if two organisms show similarities in structure or function, they are supposed to be evolved from common ancestors. The structures in different organisms which have similarity in their structure and anatomy represents homology and indicate divergent evolution. On the other hand, structures such as wings of butterfly and birds, eye of octopus and mammals represents analogy, performing similar functions, but not anatomically similar. Again the remnants of organs which were complete and functional in their ancestors represents vestigeal organs. The study of vestigeal organs offer an evolutionary explanation of such rudimentary vestiges by stating that adaptations to new environment of the organism have made these structures reductant. The rudiment of the reptilian jaw apparatus, the rudiment of the hind limbs of python and Greenland whales are some of the examples of vestigeal organs).

There is only 1 amino acid difference between humans and chimps when making up the cytochrome C protein used in the ETC of cellular respiration $\rightarrow$ Biochemical evidence (At the molecular level, the proteins found in the blood of man and chimps are similar, suggesting their ancestral relationship. The classic example of biochemical evidence is the difference in just one amino acids in the cytochrome C protein of humans and chimps. The base pair substitution is due to mutation that is the cause of difference in amino acid and showed that the two species diverged along different directions. The different existing configuartions of amino acids do not affect the function of the protein, cytochrome C to a greater extent, which indicate the base pair substitution is a process of random mutations but not selection).

Archaeopteryx organism shows as an intermediate species between reptile and birds $\rightarrow$ Fossil evidence (Fossils are the remains and /or impressions of organisms that lived in the past last few centuries. Phylogeny, the evolutionary history of the organism, can sometimes be reconstructed with te help of fossils. Besides form and structure, the habits and behavior of extinct species can be inferred from the well preserved fossils. Fossils also indicate crossing links between two groups of organisms. Archaeopteryx shows features of both reptiles and birds. The reptilian characters includes- (i) The body axis is more or less lizard like. (ii) A long tail is present. (iii) The jaws are provided with similar teeth. (iv) Presence of free caudal vertebrae as found in lizards. (v) The hand bears typical reptilian plan and finger terminates in a claw. The avian features includes- (i) Presence of feathers on the body. (ii) The two jaws are modified into a beak. (iii) The fore limbs are modified into wings. (iv) The hind-limbs are built on the typical avian plan. (v) An intimate fusion of the skull bones as seen in the birds).

Marsupials are found mostly on the continent of Australia $\rightarrow$ Biogeographical evidence (The study of patterns of distribution of animals and plants in different parts of the earth is called biogeography. The process of evolution of different species in a given geographical area starting from a point and literally radiating to other areas of geography is called adaptive radiation. The wide range of Australian marsupials also support the phenomenon of adaptive radiation. A number of marsupials, each different from the other, like Koala, kangaroo, Wombat, etc originated from an ancestral marsupial, but all within the same island of Australia).

Humans and rabbits have gill slits during various stages of development $\rightarrow$ Embryological evidence (Embryological support for evolution was proposed by Ernst Haeckel based upon the observation of certain features during embryonic stage common to all vertebrates that are absent in adult. For example, the embryos of all vertebrates including human develop a row of vestigeal gill slits behind the head, but it is a functional organ only in fish and not found in any other adult vertebrate. The sequence of embryonic development in different vertebrates show striking similarities. Gill clefts and notochord appear in the embryonic development of all vertebrates from fishes to mammals. The notochord is replaced by vertebral column in all adult vertebrates. Similarly, gills are replaced by lungs in adult amphibians and mammals. Such similarities in embryonic development once again reinforce the idea of evolution from common ancestors).