Human Evolution Flashcards: Hominids, Phylogeny, and Tool Cultures

A comprehensive set of practice flashcards covering hominid/hominin classification, phylogeny, cranial/cerebral trends, dentition, skeletal adaptations for bipedalism, hands/digits, and major stone tool cultures (Oldowan, Acheulian, Mousterian, Upper Paleolithic), plus cultural developments and lifestyle shifts.

What family includes humans and the great apes and shares the most recent common ancestor with humans?

Hominidae (Hominids)

Which subfamily includes modern and extinct chimpanzees, gorillas, and humans?

Homininae.

What is the tribe Hominini (Hominins) and name some key examples?

Hominini includes extinct ancestors of humans and modern humans. Examples: Australopithecus afarensis, Australopithecus africanus, Paranthropus robustus, Homo habilis, Homo erectus, Homo neanderthalensis, and Homo sapiens.

What genus includes Homo sapiens and some extinct ancestors?

Genus Homo.

Name some key species/examples listed under Hominini (Hominins).

Australopithecus afarensis, Australopithecus africanus, Paranthropus robustus, Homo habilis, Homo erectus, Homo neanderthalensis, Homo sapiens.

What is the purpose of phylogenetic trees?

To represent evolutionary relationships between organisms.

How is relatedness inferred on a phylogenetic tree?

Species with more recent common ancestors are more closely related; less recent common ancestors indicate greater divergence. Trees are hypotheses, not absolute facts.

How does DNA sequence similarity relate to phylogeny?

The more similar the DNA sequences, the more closely related the organisms are, indicating less time since their common ancestor or divergence.

According to the Marking Key, which is more closely related to modern humans: Australopithecus afarensis or Paranthropus boisei?

Paranthropus boisei is more closely related to modern humans; afarensis is more distantly related.

What distinguishes Paranthropus specimens in relation to Homo, and what feature marks them?

Paranthropus specimens are considered more ape-like and not direct descendants of Homo; they are distinguished by a sagittal crest on the skull.

What does the genus Homo signify in terms of features?

Larger brains, proficient bipedalism, well-developed precision grip, and tool-making abilities.

What is the ape average cranial capacity?

400–500 cm³.

What is the average cranial capacity for modern humans?

About 1350 cm³ (range 900–2200 cm³).

Cranial capacity for Australopithecus afarensis?

Approximately 430 cm³.

Cranial capacity for Australopithecus africanus?

Approximately 480 cm³.

Cranial capacity for Paranthropus robustus?

Approximately 520 cm³.

Cranial capacity for Homo habilis?

Approximately 590–610 cm³.

Cranial capacity for Homo erectus?

Approximately 1050 cm³ (range 750–1250 cm³).

Cranial capacity for Homo neanderthalensis?

Approximately 1485 cm³ (range 1400–1500 cm³).

Cranial capacity for Homo sapiens?

Approximately 1350 cm³.

What is the general trend in cranial capacity during hominin evolution?

A gradual increase in cranial capacity.

What percentage of the total cortical surface does the human frontal lobe constitute compared to apes?

Humans: about 47%; apes: about 33%.

What is the effect of cerebral cortex convolutions on brain surface area?

Convolutions increase the surface area of the brain and cerebral cortex by about 50%.

What is the position of the foramen magnum in humans vs. apes?

Humans: moved forward to a central position underneath the skull; apes: located at the rear of the base of the skull.

How does the spinal curvature differ between humans and apes, and what is the advantage?

Humans have an S-shaped (double) curvature; apes have a smooth C-shaped curve. The S-curve improves balance and supports upright posture.

Describe the human pelvis in comparison to the ape pelvis and its advantage.

Humans have a broader, shorter, bowl-shaped pelvis, which supports abdominal organs, stabilizes bipedal locomotion, and accommodates a developing fetus in females.

What is the carrying angle, and which lineage exhibits it?

The carrying angle is the angle formed as the femurs converge toward the knees; humans have it to aid weight distribution and stability in an upright gait, while apes lack it.

How do the legs and feet of humans differ from those of apes?

Humans: longer legs, arches in the feet, robust non-opposable big toe, large calcaneus. Apes: legs shorter than arms, flat feet with a prehensile, sideways-facing big toe, curved phalanges.

Where is the center of gravity located in humans versus apes?

Humans: at pelvis level; apes: at chest level.

What evidence supports an arboreal/brachiation lifestyle in Australopithecus afarensis and Homo naledi?

Long, curved fingers and a highly mobile shoulder joint suggest arboreal capabilities and brachiation.

What is Oldowan tool culture, and when did it occur?

Simple tools around 2.6 to 1.4 million years ago; mainly associated with Homo habilis (with early evidence from A. afarensis and A. garhi).

Describe Oldowan tools.

Simple river-worn pebbles crudely fashioned with minimal flakes removed; cores with cutting edges; include choppers, scrapers, flakes, and chisels.

What manufacturing approach characterizes Oldowan tools?

Striking one stone with another to sharpen or shape; minimal flaking; use of surrounding materials.

What were Oldowan tools used for?

Cutting food/meat, skinning, breaking bones, cracking open nuts/roots, warding off predators; scrapers required a precision grip.

When did Acheulian tool culture arise and with which hominin is it mainly associated?

Approximately 1.9 million to 100,000 years ago; mainly associated with Homo erectus.

What is a typical Acheulian hand axe like?

A teardrop-shaped tool flaked around all edges (bi-faced); mainly worked from a core stone.

Describe Acheulian manufacturing techniques.

Flaked on both sides, first in one direction and then the other; the core stone was the main material.

What were the uses and significance of Acheulian tools?

Hunting and cutting meat, butchering, skinning, digging, making traps; may have served as a metatool to fashion other tools; reflects increased cognitive abilities and social organization.

When did Mousterian tool culture appear and with whom is it associated?

Approximately 400,000 to 40,000 years ago; associated with Homo neanderthalensis.

What is the Mousterian technique Levallois?

A disc-shaped core is prepared and struck to produce flat flakes with sharp edges; allows controlled flake production.

What is Hafting in Mousterian tool culture?

Attaching flake tools to handles, spears, or arrows.

What were Mousterian tools primarily used for?

Spears for hunting large animals; hand axes; scraping hides; making other tools.

What is the Upper Paleolithic tool culture, and when did it occur?

Homo sapiens tools from about 50,000 to 10,000 years ago; included finer blades and projectile weapons.

Name the subcultures/types of the Upper Paleolithic tool era.

Aurignacian, Solutrean, Magdalenian.

What materials and techniques characterize Upper Paleolithic tools?

Bones, antler, ivory in addition to flint/stone; blades; willow-leaf and laurel-leaf points (Solutrean); burin tools in Magdalenian; punch blade technique.

What were the uses and significance of Upper Paleolithic tools?

Spear tips, blades, tools for making other tools; needles for sewing; fishing hooks; harpoons; projectile weapons; marked a cultural explosion and advances in technology.

What are the general trends in tools across hominins?

Increased manipulation and complexity of tools; greater variety of materials; improved workmanship and specialization.

Which hominin is first associated with the use of fire?

Homo erectus.

What are some benefits of fire for early humans?

Warmth, protection against predators, illumination, cooking food, hardening wood spears, aiding in hunting.

Which hominin is first linked to ceremonial burial, and what does this imply?

Homo neanderthalensis; burial with items suggests beliefs in life after death and more complex social behavior.

Which hominin is first associated with artistic expression, and what forms can art take?

Homo sapiens; forms include portable art, cave/mural art, and adornments like shell beads and ivory figurines.

How did language develop across hominins?

Early Homo (habilis) shows limited speech-area development; Homo erectus could have had relatively complex language; Homo neanderthalensis had simple language and music; Homo sapiens developed complex language.

What is the Hunter-Gatherer vs Agricultural/Pastoralist lifestyle distinction, and why does it matter?

Hunter-Gatherer: nomadic, small groups, low density, diverse food, few possessions, lower disease spread. Agricultural/Pastoralist: sedentary, larger populations, higher density, less variety in diet, more possessions, higher disease risk. This shift enabled the Neolithic Revolution.

What is the Neolithic Revolution and its significance?

Transition to farming that provided a reliable food source, enabling permanent settlements and the rise of towns and villages.

Explain the brain–tool–lifestyle feedback loop in human evolution.

Increased brain size improves tool-making, which improves food gathering and diet quality, freeing energy for even larger brain growth, reinforcing biological and cultural evolution.

What is the overall impact of tool development on lifestyle and culture?

Increased collaboration, division of labor, and environmental manipulation to meet human needs; tools shape social organization and survival strategies.