Our Origins

Question 1

What are Hominids

Answer 1

They are humans and Bipedal (walk on two legs) ancestors
Which separated from chimpanzees at around 6.5Ma

Question 2

What is a special feature about the Hominidae family

Answer 2

Are primates with very large brains and arboreal (tree-living)

Question 3

Currently the Hominids comparise of 8 extant (living) species in 4 genera
What are they

Answer 3

• Gorilla
• Homo (ancient and modern humans and ancestors)
• Pan (chimpanzees)
• Pongo (orangutans)

Question 4

When was the last split from the great apes

Answer 4

About 8.8 million years ago

Question 5

What lineage did Homo Sapiens come from

Answer 5

Homo Erectus

Question 6

The fossil record of the earliest hominids is not good - hence we cannot infer much
Our closest relatives (H.sapiens neanderthalensis, archaic H.sapiens and H.erectus) all had what common features

Answer 6

Large brain, small teeth, and obligate bipedalism (compulsory two-leggedness)

Question 7

Hominids where only found in Africa until

Answer 7

Around 80 thousand years ago

Question 8

When did Oppenheimer (2012) conclude that anatomical modern humans left Africa
Where did they go after Africa

Answer 8

• About 72,000 years ago (after a false earlier start)
• They then spread around the Indian Ocean towards Australasia
• After this, some ‘colonists’ left S.Asia to eventually disperse into Europe

Question 9

What is phylogeograpgy

Answer 9

• As a population spread from origin, difference can arise
• By tracking the changes we can reconstruct the pattern and timing of spread
• It is the geography of evolution

Question 10

What conditions were suspected to enable the movement of the Hominoids once they left Africa

Answer 10

It was during a Glacial period
So lots of sea ice, removed potential sea barriers

Question 11

The Neanderthals where a sub-species of Homo sapiens but where thought to have gone extinct
What are key features of the Neanderthal species?

Answer 11

Neanderthals (ancient humans) which lived in Eurasia 250,000-40,000 yrs ago
They were stockier than modern humans with shorter legs and larger bodies
Interbreeding between Neanderthals and modern humans is thought to have occured causing the two sub-species coales into one

Question 12

What is included within the Large Herbivorous Vertebrate group

Answer 12

Sloths, giant kangaroons, moa, wolly mammoths, stright-tusked elephants, steppe rhino, woolly rhino and giant deer etc
They ate (cropped) vegetation, creating large open spaces and creating an environment with relatively few forest fires

Question 13

What is the link between Large Herbivorous Vertebrates and the arrival of Homosapiens

Answer 13

The Large Herbivorous Vertebrates (and the predators that fed on them) largely disappeared (megafaunal extinction) upon arrival of humans
Often thought to be due to human hunting (or possibily environmental change too but unlike cuz doesn’t align with an interglacial)

Question 14

Why is the extinction of Large Herbivorous invertebrate thought to be the fault of humans

Answer 14

• Timing of human arrival and extinction across the glove too much of a coincidence
• No comparable extinction event in marine realm (untouched by humans)
• End-pleistocene climate change did happen but changes of greater magnitude did not cause big extinction pulses
• The pattern of extinction is very odd

Question 15

What types of mammals went extinct due to human invasion in the Late Pleistocene

Answer 15

Very large mammals

Question 16

What was the impact of fruit bearing tree due to extinction of large herbivourous invertebrates

Answer 16

Many of these fruits had mechanism which were clearly designed to have their seeds dispersed by these invertebrates when eating the fruit
Many of these fruits now just rot on the tree or on the ground - indicting the the organisms which originally ate these fruits have now disappeared
These plants are now reliant on humans and without humans would have gone extincted

Question 17

In some forests you see these ‘paranoid trees’ which have thought to be a relic of the previous extinct megafauna, why?

Answer 17

The Honey Locust tree has spines up its bark to protect against predators from eating/destroying it
Apart from there are no predators large enough to do that now
These spins are thought to be relics of being eaten by the giant sloth

Question 18

Another hangover from the extinction of large herbivourous invertebrates is the development of soggy tundra

Answer 18

When the megafauna existed there was very much a mosaic of many different types of environments due to them being generalists with mixed food diets
Modern fauna instead are relatively specialists with monocultural diets created a stripe pattern environment
This created an environment dominated by mosses and trees etc which don’t return as much water to atmopshere, they are a lot wetter - hence soggy tundera