Evolution Flashcards
Q: Cornerstone of modern biology?
Evolution.
Q: Mechanism driving evolution? How does it work?
-Natural selection is the mechanism that drives evolution.
-Random genetic mutations increase genetic diversity.
-Advantageous mutations result in the survival of the fittest.
-As a result, species adapt to (changing) environments.
Q: Evidence for evolution?
-Progressions of species changing over time (fossil record shows progression from simple to more complex and specialized organisms over time).
-Similarities between species showing common ancestry.
-Anatomy, e.g., remnants of past generations within species.
-Embryology, e.g., all vertebrate embryos, including humans, exhibit gill slits at some point in early development.
-Biogeography
-DNA analysis
Q: Only evolutionary process that leads to adaptations?
Natural selection
Q: Adaptive radiation
-process in which organisms diversify rapidly into a multitude of new forms, particularly when a change in the environment opens up new niches, making new resources available, creating new challenges.
-e.g., diversified lemur species in Madagascar
-often follows mass extinctions
Q: Does evolution favor generalization or specialization?
Specialization.
There’s a tendency for life forms to fill all available niches.
Specialization often confers an advantage upon a species in its struggle for existence.
Specialization may subdivide a single niche into many new niches.
Q: Advantages/disadvantages of specialists and generalists?
-Specialists thrive when conditions are just right. They fulfill a niche and are very effective at competing with other organisms.
-Generalists respond much better to changes/uncertainty. These species usually survive for very long periods because they deal with unanticipated risks better. But unlike specialists, they don’t maximize their current environment, because they don’t fill a niche where they could be more successful.
-An environment with more competition breeds more specialists. Rainforests have huge diversity and competition and therefore many specialist species.
Q: Analogous structures
similar structures that evolved independently in two living organisms to serve the same purpose.
Q: Biodiversity
Is the variety and variability of flora and fauna on earth.
Q: Biological evolution
any genetic change in a population that is inherited over several generations. These changes may be small or large, noticeable or not so noticeable.
Q: Coevolution
The process of reciprocal evolutionary change that occurs between pairs of species or among groups of species as they interact with one another; two (or more) species reciprocally affect each other’s evolution; the evolutionary change of one species triggered by interaction with another species.
Q: Convergent evolution
unrelated species can develop similar traits as the process of natural selection results in the same solution to a similar problem.
Q: Is extinction natural?
Gradual rates of extinction are natural but rapid rates of extinction are not.
Q: Genetic diversity
the total number of genetic characteristics in the genetic makeup of a species. It is distinguished from genetic variability, which describes the tendency of genetic characteristics to vary.
Q: Genetic drift
a change in the number of times you might see a certain trait in a population due to chance or random events.
