Bukwa
Basic information
Sample name: Bukwa

Reference: S. Cote, J. Kingston, A. Deino, A. Winkler, R. Kityo, and L. MacLatchy. 2018. Evidence for rapid faunal change in the early Miocene of East Africa based on revised biostratigraphic and radiometric dating of Bukwa, Uganda. Journal of Human Evolution 116:95-107 [ER 3995]
Geography
Country: Uganda


Coordinate: 1° 17' 6" N, 34° 47' 5" E
Coordinate basis: stated in text

Time interval: Early Miocene

Min Ma: 19.16

Age basis: Ar-Ar

Geography comments: "on the northeastern slopes of the Mount Elgon volcano... approximately 2.25 miles east of the town of Bukwa"
"The site has two main fossil localities - Bukwa I and Bukwa II. Although Bukwa I was discovered first... almost all of the mammalian fossils were collected in subsequent years from the Bukwa II locality"
there is a more reliable Ar-Ar date of 19.16 +/- 0.14 Ma for a lava flow at the top of the section, plus an Ar-Art date of 19.0 +/- 1.1 Ma for another one at the bottom of the section that is not useful here

Environment
Lithology: siliciclastic (mixed)

Taphonomic context: lake deposit

Habitat comments: "Bukwa I is located on the southeastern slope of Kwongori Hill and consists primarily of paleosols that have produced few vertebrate fossils but numerous plant fossils. Bukwa II is comprised of a series of lacustrine horizons exposed in gullies at the base of the western side of Kwongori Hill" and specifically "a series of lacustrine claystones and siltstones, paleosols, and subaerial and epiclastic tuffs containing invertebrate, plant, and vertebrate fossils"

Methods
Life forms: primates,rodents,ungulates,other large mammals,other small mammals

Sampling methods: screenwash

Sample size: 85 specimens

Years: 1965, 1966, 1967, 1968, 1970, 1997, 1998, 2002, 2003, 2015

Sampling comments: "a Makerere University expedition led by Walker and Henderson in December 1965 uncovered proboscidean remains at Bukwa I... The following year, Walker and Bishop visited the site and found additional fossils from a second collecting area located approximately 100 m away, which they designated Bukwa II. Excavations of the Bukwa II locality took place in 1967, 1968, and 1970... Pickford and colleagues from the Uganda Palaeontology Expedition visited Bukwa in 1997 and 1998 and collected plants, gastropods, and some mammals... We visited Bukwa in 2002, 2003, and 2015 to collect fossils and samples for radiometric dating. Our paleontological surface collections were augmented through wet-screening sediments from the green clay deposits in the upper portion of the lacustrine sequence at Bukwa II"

Metadata
Sample number: 4411

Contributor: John Alroy

Enterer: John Alroy

Modifier no: John Alroy

Created: 2024-10-27 00:59:48

Modified: 2024-10-27 01:18:36

Abundance distribution
30 species
16 singletons
total count 85
extrapolated richness: 89.7
Fisher's α: 16.525
geometric series k: 0.9179
Hurlbert's PIE: 0.9315
Shannon's H: 3.0057
Good's u: 0.8129
Each square represents a species. Square sizes are proportional to counts.
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