Chapter 11 - Becoming human Flashcards
(34 cards)
Homo Sapiens
The Species name for modern humans
Taxon (pl. taxa)
a unit of biological classification into which related organisms are classified. Taxa are arranged in a hierarchical rank from kingdom down to species, where members of a specific taxon typically share certain morphological characteristics
Mammals
warm-blooded vertebrates belonging to the taxonomic class Mammalia that have mammary glands, hair/fur, three middle ear bones, and one lower jawbone
Primates
the highest order of mammals, comprised of about 400 different living species who share a number of features including opposable digits and binocular vision
hominoids
members of the superfamily Hominoidea that includes apes and humans
Hominins
members of the taxonomic tribe hominini that includes modern humans and our upright-walking ancestors
cranium
the part of the skull that covers the brain
prehensile
the ability to grasp objects
opposable digit
a digit (either the thumb, big toe, or both) that is able to touch all the other digits on the same appendage
precision grip
a type of grip involving the tips of the thumb and finger, used by primates (to varying extents) for precise manipulation of objects of various sizes
power grip
a type of grip involving the palm and fingers, used by primates (to varying extents) for moving and manipulating objects. The power grip generates more force due to the significant use of the palm
canine teeth
a type of tooth in mammals that is relatively long and pointed
foramen magnum
the hole in the base of the skull through which the spinal cord passes. A more centralised foramen magnum indicates bipedal locomotion
Brow ridge
a bony ridge above the eye sockets. It is found in all primates, but is greatly reduced in Homo sapiens
Sagittal crest
a ridge of hard bone running lengthwise (front to back) along the top of the skull. A pronounced sagittal crest indicates strong jaw muscles.
femur angle
the angle between the top and bottom of the femur when standing. It is greater in hominins when compared to other primates
genus (pl. genera)
a taxonomic rank above species and below family. Modern humans belong to the genus Homo
Biped
an individual that moves on two legs (upright-walking)
arboreal
living in or amongst trees
cerebrum
the largest part of the brain, which comprises two-thirds of the brain’s entire weight and is responsible for a large range of vital functions including sensory processing, motor control, and visual and spatial learning
arm to leg ratio
the ratio of arm length to leg length. Tree-dwelling hominids have longer arms and shorter legs, or a larger arm to leg ratio
inference
conclusions or assumptions reached by analysing and extrapolating from evidence
transitional fossil
a fossil that shows traits that are common to both its ancestral group and its descendant group. They are particularly important when the descendant species is physically very distinct from the ancestral species, such that the transitional fossil can help demonstrate evolutionary changes between the two
interbreeding
refers to the mating between different species (e.g. between *Homo sapiens** and other closely related species such as Neanderthals and Denisovans). Also known as crossbreeding.