Lab 10 Flashcards
Homo erectus
An extinct human species that lived from ~1.9 million to 143,000 years ago. Known for its large geographic range and anatomical variability.
Homo ergaster
Sometimes considered a separate species from Homo erectus, mainly used to refer to African specimens with slightly different anatomical traits.
Sagittal Keel
A thickening or ridge of bone along the midline of the top of the skull, commonly seen in Homo erectus but absent in modern humans.
Supraorbital Torus
A prominent brow ridge found above the eyes, larger in Homo erectus than in Homo sapiens.
Post-orbital Constriction
Narrowing of the skull just behind the eye sockets; present in Homo erectus and absent in Homo sapiens.
Nuchal Torus
A horizontal ridge of bone at the back of the skull where neck muscles attach; more pronounced in Homo erectus.
Acheulean Tools
Bifacially flaked stone tools like handaxes and cleavers associated with Homo erectus; more complex than Oldowan tools.
Oldowan Tools
Earlier, simpler stone tools made by removing flakes from only part of a stone’s surface.
Movius Line
A theoretical boundary separating regions (mostly in East Asia) where Acheulean tools are rare or absent, possibly due to raw material differences or alternative technologies like bamboo.
Bifacial Core Reduction
A technique of flaking stone tools from both sides of a core to produce tools with a more symmetrical and sharper cutting edge.
Handaxe
A teardrop-shaped bifacial stone tool used for cutting; characteristic of the Acheulean tradition.
Cleaver
A bifacial tool with a broad, straight cutting edge instead of a point, also part of the Acheulean toolkit.
Cutting Edge-to-Weight Ratio
A measurement used to evaluate how efficient a tool is by comparing its cutting edge length to its weight.
Resharpening (Retouching)
The process of reworking a tool’s edge by flaking off small pieces to expose a fresh sharp edge.
Platform Edge
The base of a flake where it was struck from the core; often steep and not usable for cutting or retouching.
Refit Sequence
A reconstruction of the order and technique used to flake a core by reassembling the flakes; used to evaluate the complexity of toolmaking.
Economics of Lithic Raw Material
The study of how hominins used and transported stone tools and materials to balance tool effectiveness and carrying cost.
Cognitive Cost of Technology
The mental effort and planning needed to create more complex tools like Acheulean handaxes, used to assess the trade-offs of adopting new technologies.
