HUMAN EVOLUTION Flashcards
(120 cards)
What is human evolution?
The extensive process by which modern humans developed from primate ancestors over approximately six million years, characterized by significant physical and behavioral changes.
(Smithsonian Institution, 2024)
What order do primates belong to?
A diverse order of mammals that includes lemurs, lorises, tarsiers, monkeys, and apes (including humans).
(Blaxland, 2018)
When did primates first appear?
More than 55-65 million years ago.
What are the key characteristics of primates?
- Arboreal Origins
- Enhanced Cognitive Abilities
- Sensory Adaptations
- Social Structures
What is the significance of enhanced cognitive abilities in primates?
Facilitates advanced problem-solving and social interactions.
(Brainard & Henderson, 2025)
What adaptations do primates have for their sensory systems?
Keen vision, often with depth perception and color vision.
What type of social structures do primates exhibit?
Complex social behaviors, forming various group dynamics that enhance survival and reproduction.
What are prosimians?
Among the earliest primates, having evolved approximately 55 to 65 million years ago.
What are the physical characteristics of prosimians?
- Generally small-bodied
- Predominantly nocturnal
What sensory adaptations do prosimians possess?
- Large, forward-facing eyes for binocular vision
- Strong reliance on the sense of smell
What are the locomotor adaptations of prosimians?
- Grasping hands and feet with long fingers and toes
- Most have nails instead of claws
What are typical dietary habits of prosimians?
Omnivorous, consuming insects, fruits, leaves, and occasionally small vertebrates.
What are the examples of prosimians?
- Lemurs
- Tarsiers
- Lorises
When did early anthropoids emerge?
Approximately 35 to 40 million years ago during the late Eocene to Oligocene epochs.
What significant anatomical adaptations did early anthropoids develop?
- Larger brains relative to body size
- Forward-facing eyes with binocular vision
- Fully opposable thumbs
What lifestyle changes did early anthropoids undergo?
Transitioned from nocturnal to diurnal lifestyles.
What is the significance of the evolutionary transition from prosimians to anthropoids?
Marked a significant divergence from their prosimian ancestors.
What are New World monkeys characterized by?
- Grasping tails
- Broad, flat noses
- Exclusively tree-dwelling
What are Old World monkeys characterized by?
- Non-prehensile tails
- Narrower noses
- Adapted to both arboreal and terrestrial environments
When did apes or hominoids emerge?
During the Miocene epoch, approximately 23 to 5.3 million years ago.
What is a key evolutionary trend in primates?
Increased brain size associated with cognitive advancements.
What adaptations have primates made for vision?
- Development of forward-facing eyes
- Trichromatic color vision for detecting ripe fruits and predators
What are flexible shoulder adaptations in apes used for?
Facilitates brachiation—a form of locomotion involving swinging from branch to branch.
What dietary evolution is observed in primates?
From simple insect-based diet to omnivorous flexibility.