Hominin Evolution and Hominid Fossil Studies

Vocabulary-style flashcards covering hominin evolution, specific fossil discoveries like Lucy and Mrs. Ples, the transition to the genus Homo, and human migration theories.

Australopithecines

A group of hominins that lived on the African continent between $4.0$ and $1.0\,mya$ and split into gracile and robust forms due to dietary and habitat changes.

Gracile Form

A thin and slender category of Australopithecines with smaller teeth and chewing muscles, exemplified by Australopithecus africanus and Australopithecus sediba.

Robust Form

A hominin category characterized by very large jaws and teeth, commonly placed in the genus Paranthropus, which became extinct approximately $1.0\,mya$.

Australopithecus afarensis

A species existing between $4.0$ and $3.0\,mya$ with ape-like features and small cranial capacity; notable examples include Lucy from the Awash valley in Ethiopia.

Lucy

A $3.2\,million$ year old Australopithecus afarensis skeleton discovered in 1974 by Donald Johanson, Yves Coppan, and Tim White, providing strong evidence for bipedalism via the foramen magnum position.

Taung Baby

The fossil of an Australopithecus africanus infant discovered by Raymond Dart in 1924, featuring a forward-positioned foramen magnum and human baby-like dentition.

Mrs. Ples

An adult Australopithecus africanus fossil discovered by Robert Broom in the Sterkfontein Caves, estimated to be $2.6\,million$ years old.

Little Foot

An Australopithecus africanus fossil dated between $3.9$ and $4.2\,mya$, discovered by Ron Clark, showing skeletal adaptations for both ground walking and tree climbing.

Laetoli Footprints

A set of fossilized footprints discovered by Mary Leakey in 1978 in Tanzania, dated to $3.6\,mya$, showing bipedal walking with the big toe in line with the foot.

Australopithecus sediba

A transitional fossil dated between $2.0$ and $1.7\,mya$ discovered by Lee Berger's son, considered a missing link between the Australopithecus and Homo genera.

Prognathism

The positional relationship of the mandible or maxilla to the skeletal base where either jaw protrudes beyond a predetermined imaginary line in the coronal plane of the skull.

Homo naledi

A primitive species discovered by Prof Lee Berger in 2013, characterized by a tiny brain, curved fingers, and intentional body placement deep underground.

Homo habilis

Known as the 'handy man,' this species existed between $2.4$ and $1.5\,mya$ and was the first recognized tool maker, possessing a larger brain than Australopithecus.

Oldowan stone tools

Basic stone tools associated with Homo habilis, used for scavenging and basic woodworking.

Homo erectus

A hominin emerging $1.5\,mya$ that used Archeulian tools and was the first to use fire, which allowed for cooked food and migration out of Africa.

Archeulian tools

Larger and sharper stone tools developed by Homo erectus for the purpose of hunting.

Cro-Magnons

Modern Homo sapiens known for advanced behaviors such as making bone flutes, burying the dead, decorating cave walls, and baking ceramic figures.

Multi-regional Hypothesis

A theory suggesting modern humans evolved from Homo erectus in various locations simultaneously with gene flow between populations.

Out of Africa Hypothesis

A theory stating modern humans evolved in Africa about $200,000$ years ago and migrated in a second wave $50,000$ years ago to replace other hominins.

Mitochondrial Eve

The genetic matrilineal ancestor in Africa associated with the Out of Africa model, traced back through $mtDNA$ to approximately $150,000$ years ago.

San

The world's oldest extant group, having lived in South Africa as hunter-gatherers for approximately $20,000$ years.