Biological Evolution of Humans Flashcards
Hominid
All extinct and living great apes.
Hominin
Modern humans or our extinct ancestral relatives.
Prognathism
The degree at with the maxilla and mandible extend beyond the face
Biological evolution
Changes in traits/phenotypes that are due to changes in allele frequency/genetic changes passed on in genes from one generation to the next.
Homo habilis
Age: between 2.4 and 1.6 mya
Locomotion: bipedal
Diet: Scavengers - Softer plants and some meat
Habitat: Wooded savannah
Cranial capacity: 600 - 700 cm3
- Capable of rudimentary speech
- Precision grip
Homo erectus
Age: 1.9 mya to 30,000 years ago
Locomotion: Fully bipedal
Diet: High quality omnivore
Habitat: open grasslands
Cranial capacity: 750 - 1300 cm3
Homo neanderthalensis
Age: 350 - 28 kya
Locomotion: Fully bipedal
Diet: Varied
Habitat: Varied
Cranial capacity: 1200 - 1750 cm3
Homo sapiens
Age: 200 kya to present
Locomotion: Fully bipedal
Diet: Omnivorous
Habitat: varied and diverse
Cranial capacity: 1500 - 1350 cm3
Cranial capacity
The volume of the cranium/brain case - usually given in cm3
Endocranial
Within the skull. Features of the brain inferred by endocast impressions and volume.
When did Hominin evolution begin?
approx 7 million years ago
How has the saggital crest evolved?
Reduces as muscles associated with chewing decreases as their diets change from tough plant material to softer foods
How has the brow ridge evolved?
Reduces as diet changes from tough plant material to softer foods
How has foramen magnum evolved?
All are more central than chimpanzees, and almost certainly our most recent common ancestor. Fully centred in later Homo sp.
How has nuchal crest evolved?
Gradually reduces in size as
species become fully habitually/obligately bipedal.
