COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE
Horse Evolution
BY DR. POULAMI ADHIKARY MUKHERJEE ASSISTANT PROFESSOR DEPARTMENT OF ZOOLOGY NARAJOLE RAJ COLLEGE
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE
Horses
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE Equus caballus
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE Equus burchelli: the zebra
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE Horse-Zebra hybrid Shows that genes are discrete and not blended by genetic recombination.
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE
1870 The extinct quagga (1883), related to today's plains zebras.
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE
“Family tree” of the horses
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE Ungulate Toes
Artiodactyls: Perissodactyls: even-toed odd-toed
Bovine and swine Horse and rhinoceras
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE
Horses reduced their toes from five to one, while also lengthening the bones, during their evolution.
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE
Hyracotherium Miohippus Merychippus Equus
Hind feet left, front feet right.
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE Hyracotherium or Eohippus from the Eocene, a forest browser
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE Orohippus from the late Eocene, also a forest browser
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE Miohippus from the Oligocene. Forests were shrinking, grasslands were expanding.
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE
Merychippus from the Miocene, a plains grazer
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE
The modern horse Equus from the Pleistocene and Recent
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE
Evolutionary trends in horses and many other ungulates
• Reduction in toes • Elongation of legs by standing on the toes • Increased body size • Elongation of the muzzle • High crowned, specialized teeth
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE Environmental Causes of Evolutionary trends in horses and many other ungulates • Need for greater speed and body size to escape predators. • Cooling climate during the Cenozoic replaced forests with grasslands. Simple hooves and elongated legs are adaptive for running in the open. Elongated muzzle to reach grass. • Grasses are high in silica. High crowned teeth are adaptive.
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE COMPILED AND CIRCULATED BY DR. POULAMI ADHIKARY MUKHERJEE, ASSISTANT PROFESSOR, DEPARTMENT OF ZOOLOGY, NARAJOLE RAJ COLLEGE
ZOOLOGY: SEM- VI, PAPER- C14T: EVOLUTIONARY BIOLOGY, UNIT 3: EVOLUTION OF HORSE