Here students can locate TS Inter 1st Year Zoology Notes 4th Lesson Animal Diversity-II: Phylum Chordata to prepare for their exam.
TS Inter 1st Year Zoology Notes 4th Lesson Animal Diversity-II: Phylum Chordata
→ The evolution of the chordates dates back to more than half a billion years.
→ Chordates are enterocoelous deuterostomes and are closely related to invertebrate group Echinodermata.
→ In higher chordates dorsal tubular nerve cord is differentiated into anterior brain and posterior spinal cord.
→ In higher chordates unique part notochord is modified (replaced) into vertebral column.
→ Pharyngeal gill slits and post-anal tail are other distinguishing features of vertebrates.
→ Urochordates and cephalochordates are the non-vertebrate chordates.
→ Major evolutionary step of chordates is appearance of ‘Jaws’.
→ Domination of the ‘Jawed fishes’ is during the Devonian period.
→ The amphibians invaded land, but they remained an imperfect group. They failed to adapt completely to terrestrial life.
→ The Golden age of Reptiles is Mesozoic era.
→ Cleidoic (shelled) eggs first time appeared in the group Reptiles.
→ Reptiles gave rise to two major groups – the Aves and the Mammalia .
→ Kidneys evolved from the primitive ‘pronephros’ to ‘mesonephros’.
→ The origin of’amnion’ and other foetal membranes in the reptiles, air sacs, feathers of birds, the hair, mammary glands and chorio – allantoic placenta of mammals are the major Bioarchitectural wonders through the course of evolution.
→ There was a tremendous ‘genetic transformation’ making man unique.
→ The gene FOX P2 is believed to play a key role in human language expression.
→ Alfred Sherwood Romer (1894-1973):
- Alfred Sherwood Romer was an American paleontologist and comparative anatomist and a specialist in vertebrate evolution.
- Alfred Romer was born in White Plains, New York, and studied at Amherst College and Columbia University, graduating with a doctorate in zoology in 1921. Romer joined the department of geology and paleontology at the University of Chicago as an associate professor in 1923.
- He was an active researcher and teacher. His collecting program added important Paleozoic specimens to the Walker Museum of Paleontology.
- In 1934 he was appointed professor of biology at Harvard University. In 1946, he also became direc tor of the Harvard Museum of Comparative Zoology. In 1954 Romer was awarded the Mary Clark Thompson Medal from the National Academy of Sciences. He was awarded the Academy’s Daniel Giraud Elliot Medal in 1956.