Evolutionary Adaptations of Giraffes

The video explains how giraffes evolved long necks through natural selection. Initially, giraffes had short necks, but as food became scarce, only those with slightly longer necks could survive and reproduce. Over generations, this led to the predominance of long-necked giraffes. The video also defines evolution as a cumulative change in inheritable traits over generations and outlines the four steps of natural selection. Key figures like Charles Darwin and Alfred Wallace are mentioned as proponents of evolutionary theory.

What is the basic definition of evolution as introduced in the video?

• A random mutation in a single generation

• The cumulative change in heritable traits over generations

• A sudden change in species characteristics

• The process of animals becoming extinct

Why did giraffes with short necks face challenges in their environment?

• They were hunted by predators

• They couldn't find water

• They couldn't reach the trees for food

• They were unable to run fast enough

What was the main environmental challenge that led to the evolution of giraffes?

• Changes in climate

• Increase in predator numbers

• Scarcity of grass on the ground

• Lack of water sources

How did giraffes with slightly longer necks manage to survive?

• They adapted to eat different food

• They formed larger herds for protection

• They migrated to a different area

• They could reach higher leaves on trees

What happens to the genetic traits of short-necked giraffes over time?

• They become dominant

• They become more common

• They disappear from the population

• They remain unchanged

What is the term used to describe the process where nature decides which traits are passed on?

• Natural selection

• Random mutation

• Artificial selection

• Genetic drift

What does 'survival of the fittest' mean in the context of the giraffe story?

• The strongest animals survive

• The animals with the most offspring survive

• The animals with the longest necks survive

• The fastest animals survive

How does the video describe the speed of evolutionary changes?

• Unpredictable and random

• Instantaneous

• Gradual over thousands of years

• Rapid over a few years

Which of the following is NOT a step in the mechanism of natural selection?

• Better adapted individuals have an advantage

• Stable populations despite many offspring

• All individuals survive regardless of traits

• Heritable variation within species

Who were the two individuals that proposed the mechanism of evolution discussed in the video?

• Gregor Mendel and Louis Pasteur

• Isaac Newton and Albert Einstein

• Marie Curie and Nikola Tesla

• Alfred Wallace and Charles Darwin