Biology - Human Story essays

Biology - Human Story essays 1) Using appropriate example define what is a species? A species can be defined by particular structural features. Humans are species of primate mammals. They share the characteristics of this group of animals. Species can also be defined as a group of organisms that can interbreed to produce fertile offspring. 2) Give few characteristics that classify humans as Primates: Well-developed brain, well-developed eye sight, eyes forward in the face and stereo-scopic binocular vision, nose is shortened and sense of smell is reduced, thumb is opposable , flat nails (rather then claws), tendency to have single offspring births. Hominids: Brain size relative to body size is bigger than other primates, striding bipedal upright gait (human walk upright in 2 legs) adaptations for bipedalism include the location of the foramen magnum, the shape of the pelvis, the curvature of the spine, a knee that can withstand greater stress, ankles that are modified to support body weight, a foot arch that works as a shock absorber and toes that are shorter than the apes. Mammals: Fur or hair, milk-producing glands, three bones in the middle ear, specialized dentition (teeth), most mammals give birth to live young, four chambered heart. Chordate: Notochord, pharyngeal slits (gill slits), hollow dorsal nerve cord. 3) Outline features that classify human as Hominids: A prominent nose as shown by the raised bone surfaces around the nasal opening and by the bony spine at the centre of the openings base. The bone of the lower jaw is thin and may have a chin. Hominins: Striding bipedal upright gait, adaptation for bipedalism include the location of the foramen magnum, the she of the pelvis, the curvature of the spine. 4) Using one technology advances explain how there is a change in opinions of scientists about classification of primates? ...