Week 6: First hominins to Australopithecus Flashcards
1
Q
toros menalla
palaeoecology
A
- 3 phases
- lake (only aquatic fauna)
- lakeshore periodic floods these layers contain almost all vertebrate fossils
- desert (fossil dunes, uniform wind direction)
2
Q
bio chronology
toros menalla
A
- no volcanic layers for absolute dating
- ages of toros-menalla hominid site was determined based on faunal elements
- comparisons of fauna in toros menalla with east african sites (for which we do have absolute dates)
3
Q
A
4
Q
toros menalla
elephants
A
- anancus and loxodonta also appear in the “lukeino formation” in kenya. however the teeth in toros-menalla appear to be more primative than the ones found in lukeino (simpler patter, thicker enamel)
- toros menalla is therefore probably older than lukeino
5
Q
toros menalla
horses
A
- same species of hipparion as in abu dhabi (9-5.2 million years old)
6
Q
toros menalla
pigs
A
- morphology of third molars resemnles speciments of nyanzachoerus from the nawata formation in lothagam, kenya
- these layers are 5.2-7.4 million years old
7
Q
palaeoecology
5 bovid species in toros menalla
A
- reduncini (kobus)
- hippotragini (new species with primitive traits)
- bovidae (ovibovini - palaeoryx)
- antilopini
- bovini
first 3 are dominant
8
Q
palaeoecology
what do bovids indicate
A
open grassland
9
Q
palaeoecology
what do all bovid species teeth have
A
high crowns
10
Q
palaeoecology
what does no species indicate
A
closed or dry habitat
11
Q
palaeoecology toros menalla
lake
A
- tigerfish
- crocodiles
12
Q
palaeoecology toros menalla
lake shore
A
- hippopotamidae
- anthracotheriidae
- snakes
- turtles
13
Q
palaeoecology toros menalla
swamp
A
- polypterus, gymnarchus
14
Q
palaeoecology toros menalla
gallery forest
A
- colobus
15
Q
palaeoecology toros menalla
open grassland
A
bovidae
16
Q
palaeoecology toros menalla
savanna
A
- loxodonta
- anancus
- giraffidae
17
Q
diagnosis of the genus australopithecus
post cranial
A
- a postcranial skeleton adapted to habitual bipedal locomotion
- in known species forearm long relative to both upper arm and lower limb
- lumbar column longer than in recent apes
- body size dimorphism greater than modern pan and homo, less than modern gorilla
- stature ranges from ca 1.2 to 1.6 m, body mass 30-55 kg
18
Q
diagnosis of the genus australopithecus
cranial
A
brain size between 450-600 cm3
19
Q
diagnosis of the genus australopithecus
dental
A
- incisors not hypertrophied
- canine feminized
- postcanine dentition megadont relative to body size
- enamel thich relative to modern great apes
