Evolution Flashcards
What is an adaptation? Give examples.
Adaptation- An increase in genes that allow individuals in a population to better survive and reproduce in a changing environment.
Polar bears- have fur to keep warm
Arctic plants- grow close and low to the ground
Define fitness.
A measure of an organism’s ability to maximize the number of individuals surviving to a reproductive age, how well they are accustomed to their environment
Why do organisms become adapted to a certain niche over time?
Natural selection, animals that have traits that are unfavourable do not survive and only the ones with favourable traits reproduce, also increases their fitness
How important are adaptations?
Very important- the environment and all other species are constantly changing so in order for a species to keep up and not become extinct, it needs to change to survive better.
Define predation.
An adaptation to protect against predators
Ex. Spikes on a cactus help it avoid getting eaten by animals
Define protective colouration
An adaptation where an animal develops colours that mimic the environment to avoid being seen by predators
Define mimicry colouration.
An adaptation where an animal has colours that mimic the appearance of a defensive one, even though the animal is defenceless
Ex. Non-monarch butterflies have colouration that’s very similar even though they are not poisonous themselves
Define warning colouration.
An adaptation where an animal has colours that warn species they are toxic and should not be eaten
Ex. Bright colours on poison dart frogs
Define morphological adaptations.
-Any physical attribute that helps a species better survive
Ex. Fur on desert plants trap water while smooth tropical plant leaves repel water
What are behavioural adaptations?
-Changes in an animal’s behaviour throughout the year to better suit its environment
Ex. Bears hibernating in winter and squirrels storing nuts in the fall
Define beneficial, neutral and harmful mutations.
Beneficial- mutations that help an animal better reproduce
Neutral- mutations that do not affect an animal’s reproductive abilities, most mutations fall into this category
Harmful- mutations that harm an organism’s reproductive abilities
What is artificial selection?
-Controlled breeding of animals to create desirable characters in the offspring
Ex. Breeding dogs to herd sheep better
Name two pioneers of evolution and what they contributed.
How do mutations create genetic variation?
- when the genetic code mutates, new genetic information is created
- Influence both current and future generations
- Beneficial mutations allow more individuals to be produced, who will then mutate and produce more variations
How are fossils proof of evolution?
- The once living organisms show life before they evolved
- unknown organisms being found is the result of evolutionary change
- Found in locations no longer accessible to them, or kilometres under the ground
- Prove animals have actually changed
Name the term:
-the theory that fossil patterns can be explained by a disaster that wiped out most species
Catastrophism
Define uniformitarianism.
-The theory that geological changes ate slow and gradual and natural laws have not changed over time
Why do organisms get more complete as time goes on?
-Every organism develops characteristics that help it better survive, and these characteristics make them more complicated over time
Name 4 types of natural selection
Directional, Disruptive, stabilizing and sexual selection
Describe the chart for directional selection
Genetic variance shifts towards a new phenotype, line on chart would would increase as the # of organisms with that trait increases
Describe the chart for directional selection
Where extreme traits are values over intermediate traits, chart would be a U shape as the # of individuals on each side increases and the middle decreases
Give an example of directional selection
Mean width of bird beaks become larger over time to eat the harder fruits caused by drought
Give an example of disruptive selection
Large billed ducks can eat food off the bottom and small billed ducks skim food off the top, medium sized beaks can do neither
