9 - new finds in human evolution Flashcards
fossil footprints new findings (1)
Pliocene and pleistocene:
- many species of hominin coexists in eastern and southern Africa
Koobi Fora, Kenya c1.5 mya
- new footprint trails on same footprint surface
- 2 types of footprints and gait
- occurs multiple times different places
sympatric relationship between species?
Paranthropus boisei and homo erectus - lake margins important to both.
niche partitioning?
fossil footprints new findings (2)
fossil footprints:
- record information in narrow space/time window
- tends of square metres
- possibly laid down in hours or days
allows testing of hypothesis inaccessible from skeletal fossils
- hominin locomotion
- behaviour
- environmental context
fossil footprints new findings (3)
footprints formed in shallow water then gently covered by sand and silt
- 2 different patterns of bipedal walking recorded
- some more human like - homo erectus?
- some more flat and different gait - Paranthropus boisei?
New approaches: DNA
- studies of ancient DNA (aDNA) transform understanding
- mandible from tibet identified as denisovan:
(large molars, dates c160,000 ya, tens of thousands of years to adapt to high altitudes before modern humans) - modern tibetans have denisovan gene that helps cope with thin air
DNA identification (1)
- young female denisovan finger bone
- created a methylation map from DNA in finger (used human phenotype ontology of genes)
- found 56 anatomical features that differed from humans or neanderthals (34 in skull)
DNA identification (2)
girl looked similar to neanderthals (flatter cranium, protruding lower jaw, sloping forhead)
differences:
- face considerably wider than modern human or neanderthal
- arch of teeth along jaw longer
Test of method:
- compared independently to mandible
- predications from DNA matched mandible
BUT - cation as one individual
New species - homo naledi 250,000 ya
South Africa, rising star cave system, 15 inidviduals
- small stature
- small brain c500cc
Homo like features of homo naledi
cranium shape like smaller brained homo erectus and gracile face
hands and feet:
- very long digits and powerful thumb
- strong muscle attachments in index finger and thumb
- pinching ability and powerful grip
- lower limb
autralopith features of homo naledi
brain size
shoulder - strong muscle markings
pelvis - ilium flared outwards and pelvis had no curving towards front like homo sapiens
homo naledi burial and art
find information
New species - homo luzonensis 70,000 ya
- related to homo floresiensis?
- callao cave, Luzon, phillipines
- 3 individuals
- 13 bones found so far (teeth, hands and feet bones, juvenile femur)
- short stature
homo luzonensis cont
Luzon never attached to mainland phillipines - isolation?
mix of derived and primitive characteristics
teeth:
- more like modern humans
- single roots BUT very small
hands and feet:
- more like australopiths
earlier migrations our of Africa?
- complex evolutionary diversity in SEA
Homo luzonensis teeth and toes
The internal structural organisation of their teeth have more affinities with H.erectus and H.flooresiensis than with neanderthal and modern humans
H.floresiesnsis and H.luzonensis likely evolved from some H.erectus groups
- despised in various islands of region and became isolated until endemic speciation events
- (there were at least 2 during the Pleistocene)
Middle pleistocene diversity
middle pleistocene - chibanian
- c 800,000 - 150,000
- hominins originally assigned to homo heidelbergensis
Chinese chibanian fossil record
- increasing importance in showing hominin diversity
is H.heidelbergensis a useful species
- new species found in this timeframe e.g. homo naledi
New species - Homo longi (Minimum) 150,000ya
‘Dragon Man’
Qiang Ji, Heibi GEO university , China
Not Homo sapiens?
- large, square eye sockets
- thick brow ridges
- wide mouth
- massive! molars
sister taxa to Homo sapiens>
- most similar to mandible from Tibetan plateau (denisovan)
Homo longi or denisovan
similarity to mandible?
not homo longi? - massive molar
- denisovan?
- homo longi?
(read up - Qiang et al)
Homo juluensis c200,000-160,000ya
Xujiayao, northern china, number of specimens found in 70s
cranial morphology:
- very large cranial capacity
- low, wide cranial shape
- relatively large dentition with both primitive and derived characteristics
Neanderthals: ecology
traditional views of neanderthal subsistence:
- relied on big game hunting
- no hunting of small birds/animals
- lacked technology
recent findings:
- caught birds including diurnal raptors
- rabbits and hares
- rabbits and hares
- tortoises
neanderthal behaviour
use of decorative materials of biological origin?
- feathers not food
- raptor pedal phalanges
- cut marked phalanges of golden eagle
- ornamental use?
neanderthals: interpersonal violence (1)
spy cave, Belgium
- 2 neanderthal individuals
- amongst most complete examples
Taphonomic study
- cause of death
- depositional processes
3 hypotheses
- intentional burial
- interpersonal violence
Neanderthal interpersonal violence
Both skulls have trauma to top of cranium
No intentional burial?
Interpersonal violence
- can discriminate between accidental falls and homicidal blows
- Wound above HBL - blow
- wound within HBL - fall
Spy I and Spy II suggests violence not fall
Neanderthals caring for sick and injured
inferred through skeletal evidence - severe illness and injuries, health care and provisioning
e.g. feldhofer neanderthal
- severe fracture to left arm
- healed injury to frontal bone
-extensive inflammation to frontal bone
