Download Evolution Questions

Evolution Questions
What is variation in the context of biology?
It is a difference in physical trait between an individual and other individuals
What is the difference between interspecific variation and intraspecific
variation?
Interspecific is difference between individuals of different species
Intraspecific is the difference between individuals of the same species
How were the physical appearances of the tortoises and finches different,
based on the environments of the different islands?
Tortoises that long necks and legs lived in areas with tall plants while tortoises
with short legs lived in mossy areas with short plants. The finches with thick beaks
lived in areas with large, hard shelled nuts while finches with smaller beaks were
found where fruit and insects were more prevalent. Their physical appearances
seemed to match or be best suited to the environment in which they lived
What did Darwin infer from the fossil records he observed?
He inferred that similarity between fossils and existing organisms, as well as, his
discovery of marine fossils in the Andes mountains, demonstrated that the world
had changed dramatically over long periods of time and as a result, so had the
organisms that lived in it.
What is heritability?
The ability of a trait to be passed down from parent organisms to offspring
What is natural selection?
Environmental pressure and competition for resources determine which
characteristics are beneficial to an organism and which are not. The organisms
with beneficial characteristics will reproduce more than the organisms without
the favourable characteristics.
How did, what Darwin learned about artificial selection, influence his idea of
natural selection?
Biology 30
Evolution
Darwin learned that through selective breeding, the particular features of a
breed were kept, while the less desirable traits were not. Similarly, Darwin
thought, so too could the environment “select” which traits were desirable and
which were not.
What factors limit the growth of a population?
Limited resources such as food, water, shelter and disease
What are the main four principles in the theory of natural selection and what
role does each play?
Variation are the differences between individuals. Variation is what is acted
upon by natural selection
Overproduction is when more offspring are produced that can survive. This
results in a competition for resources
Adaptation is a variation that allows an organism to be better suited to its
environment in comparison to other organisms
Descent with modification: adaptations that improve an organisms’ ability to
survive and reproduce will be passed on their offspring and therefore, become
more common in the population over time.
Why must there be variation in the population in order for natural selection to
occur?
If there was no variation, there would be no difference for natural selection to
act upon. All organisms would have equal chance of survival and reproduction
Explain why the phrase, “survival of the fittest” does not accurately reflect
Darwin’s concept of evolutionary fitness.
Fitness is the ability of an organism to compete for resources and reproduce in
relation to others in the population and in a particular environment. Therefore,
fitness is relative: what may be beneficial in one environment may not be in
another. Also, the fitness of one individual, does not necessarily mean that that
one organism will survive and any individuals less suited will not. It does mean,
however, that the organism with the more beneficial trait will have a greater
chance of passing it onto offspring and therefore, over time, it is likely to
become more common in a population.
Biology 30
Evolution