Exploring Lactose Digestion and Genetics

The video explores the evolution of lactase persistence in humans, a trait allowing some adults to digest lactose. Initially, all humans were lactose intolerant after infancy, but cultural shifts like animal domestication led to genetic mutations enabling lactase persistence. This trait evolved independently in different populations, such as Europeans and the Masai, due to the selective advantage of milk consumption. Archaeological evidence supports early milk use, highlighting the gene-culture co-evolution that shaped human biology and culture.

What significant shift occurred around ten thousand years ago affecting human diet?

• Invention of the wheel

• Introduction of cooking

• Domestication of animals and crop cultivation

• Discovery of fire

What is the main sugar in milk that requires digestion?

• Fructose

• Sucrose

• Lactose

• Glucose

What happens to most mammals' ability to digest milk after infancy?

• It improves significantly

• It remains unchanged

• It decreases, leading to lactose intolerance

• It varies depending on the diet

What percentage of adults worldwide can digest lactose?

• About 50%

• About 75%

• About 33%

• About 10%

Where did researchers first identify the mutation responsible for lactase persistence?

• In South American populations

• In Asian populations

• In African populations

• In European populations

Which populations independently evolved lactase persistence?

• Europeans and Asians

• Europeans and Africans

• Asians and Africans

• North Americans and Europeans

What was a common trait among populations that evolved lactase persistence?

• Hunter-gatherer societies

• Pastoralist societies

• Nomadic lifestyles

• Agricultural societies

How did dairy consumption influence the spread of lactase persistence mutations?

• It decreased their spread

• It had no effect

• It increased their spread

• It only affected children

What is gene-culture co-evolution?

• The evolution of genes independent of cultural practices

• The influence of genetic mutations on cultural practices

• The cultural adaptation to genetic mutations

• The interplay between cultural practices and genetic evolution

What advantage did lactase persistence provide in early dairy-consuming societies?

• Improved cognitive function

• Increased height

• Enhanced strength

• Nutritional advantage during food scarcity