Kromdraai B Layer 3
Basic information
Sample name: Kromdraai B Layer 3

Sample aka: Cradle of Humankind; KB

Reference: C. K. Brain. 1975. An interpretation of the bone assemblage from the Kromdraai australopithecine site, South Africa. In Paleoanthropology: Morphology and Paleoecology (eds. R. H. Tuttle), pp. 225-243 [ER 4411]
Geography
Country: South Africa

State: Gauteng



Coordinate: 26° 0' 41" S, 27° 45' 0" E
Coordinate basis: stated in text

Scale: quarry

Time interval: Early Pleistocene

Zone: Gelasian

Section: Kromdraai

Unit number: 3

Unit order: above to below

Geography comments: the exact coordinate is given by Braga et al. (2022) but has an erroneous longitude of 27º44'60", which is interpreted to mean 27º45'0"
there are two cave sites at Kromdraai: "Kromdraai Faunal Site or KA" and "The australopithecine site... designated KB" or Kromdraai B
the material comes from the "northern wall of the exposure"
the Kromdraai deposit "was likely accumulated prior to 2 Ma" and is below a reversed polarity interval, so it is Gelasian and not Calabrian

Environment
Lithology: breccia

Taphonomic context: cave, carnivore accumulation, human accumulation

Archaeology: stone tools

Habitat comments: layer 2 is from "twelve-sixteen feet": Vrba (1981) says that the three layers "potentially included fossils from Members 1-4" as defined at that time, which corresponds to units P, Q, R, S, and T of Braga et at. (2022)
"the entire profile" including all three layers consisted of "decalcified breccia"
"the most striking feature of the bone accumulation is the extreme fragmentation of the individual pieces... It is not impossible that the cave was used a carnivore lair from time to time; the presence of carnivore coprolites tends to support this" but the fragmentation "suggests that these might well represent food remains of primitive men"
five stone artifacts are present, including "one unquestionable artifact in chert" and four "less convincing"

Methods
Life forms: carnivores, primates, ungulates, other small mammals, turtles, other reptiles

Sampling methods: quarry, screenwash

Sample size: 94 specimens

Sampled by: C. K. Brain

Years: 1955, 1956

Sampling comments: the KB site was originally collected in 1941 by Broom, who discovered the type specimen of Paranthropus robustus, but the material recorded here was collected by Brain with stratigraphic control in 1955 and 1956: no further Paranthropodus specimens were found, although the original set was "from the upper part of the deposit"
"The bone fragments were sieved" and "brushed in running water"
bones of "rodents, insectivores, and birds" representing "the prey of owls" are mentioned but not identified, although the birds are listed on the basis of Pockock (1970) without being split into layers (because Pockock failed to do so)

Metadata
Sample number: 4693

Contributor: John Alroy

Enterer: John Alroy

Created: 2025-09-03 05:02:26

Modified: 2025-09-03 05:02:26

Abundance distribution
16 species
7 singletons
total count 94
geometric series index: 35.1
Fisher's α: 5.539
geometric series k: 0.8114
Hurlbert's PIE: 0.8453
Shannon's H: 2.1850
Good's u: 0.9258
Each square represents a species. Square sizes are proportional to counts.
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