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What does comparative anatomy suggest about evolution?

We look (a bit) like our parents.

What does fossil evidence reveal about evolutionary relationships?

Multiple branch points, extinctions, and areas of uncertainty

How do DNA differences reflect evolutionary history?

DNA mutations accumulate over time, showing how species diverge from a common ancestor

What does comparing DNA sequences between species A and B show?

Their sequences diverged from a common ancestor as mutations accumulated.

What is the molecular clock?

A method using genetic differences to infer evolutionary time.

What does the ape DNA tree represent?

Evolutionary relationships inferred from DNA.

Why is sequencing DNA useful for studying evolution?

Sequencing genomes allows rapid comparison of genetic information between species.

How fast and cheap is modern DNA sequencing?

A genome can be sequenced in a few hours for £1000, with analyses completed within days.

When did Neanderthals and modern humans co-exist in Europe?

As recently as 30,000 years ago.

What key question does Neanderthal DNA address?

Whether Neanderthals and modern humans were the same or different species.

What did Noonan et al. (2006) contribute?

Sequencing and analysis of Neanderthal genomic DNA.

Who won the 2022 Nobel Prize for work on ancient genomes?

Svante Pääbo.

What is Tristan da Cuhna known for?

Being the most isolated human population on Earth.

How far is Tristan da Cuhna from major landmasses?

3400 km from Rio de Janeiro and 800 km from Cape Town.

How many surnames survive on Tristan da Cuhna?

Seven: Glass, Green, Hagan, Lavarello, Repetto, Rogers, and Swain.

How many original founders does the current population descend from?

15 ancestors (8 male, 7 female).

What major event occurred on Tristan da Cuhna in 1961?

A volcanic eruption.

Why is Tristan da Cuhna an example of the founder effect?

It was founded by a very small number of individuals.

What did Dr. Noe Zamel report about Tristan da Cuhna?

Inbreeding is so high all islanders are cousins, with siblings related by ~50 different routes

What did Y-chromosome analysis of Tristan da Cuhna reveal?

Nine haplotypes, seven linked to the seven surnames, falling into two haplogroups.

Which haplogroups were present on the island?

Haplogroup I (south-western Europe) and haplogroup R (north-western Europe).

What are two explanations for the remaining two haplotypes?

Mutation or non-paternity.

What is the asthma rate on Tristan da Cuhna?

23% have asthma; 57% show symptoms.

What might explain high asthma prevalence on the island?

Three founding ancestors were asthmatic.

Why is Tristan da Cuhna useful for studying complex disease?

The population shares common predisposition genes due to extreme relatedness.

What does human migration data indicate about genetic variation?

Most human variation (>90%) existed before leaving Africa.

Why are humans less genetically variable than chimpanzees?

Despite their tiny population, chimps retain more variation than 7 billion humans.

What does ethnicity vs. nationality illustrate?

National identity and genetic ancestry are not the same.

What can the British ancestry study tell us about variation?

What does shared DNA by descent analysis reveal?

It can identify close relatives accurately but is less precise for distant ones.

How does evolutionary medicine apply to isolated populations like Tristan da Cuhna?

Shared predisposition genes increase the ability to study genetic disease.