Mechanism of Natural Selection
A population of rabbits live in a snowy ecosystem with eagles as predators. Which trait will get passed on at higher rates:
White fur
Brown fur
White fur for camouflage
Peppered moths change over generations to camouflage with their environment to escape hungry predators.
Evolution
The _____________ of Gravity does not have evidence contradicting it.
Theory
Domestic dogs and cats are an example of ____________ selection.
Artificial
True or False: Evolution will act on a population whose traits are all the same.
False - there needs to be variation in how advantageous certain traits are for survival to reproductive age
A frog starts life as a tadpole, then grows limbs and can hop on land, then gets old and eventually dies.
Development
Which has the most evidence supporting it: a claim, hypothesis, or theory?
Theory
Give an example of a fragmented habitat.
Name a trait that would increase the fitness of a plant species.
Examples: growing more seeds, spreading out their seeds more, thorns, poison.
Fitness in biology refers to the rate at which genes get passed on to the next generation.
Holly plants start life by growing smooth leaves. If their leaves are eaten by predators, but the organism survives, it will grow back spiky leaves for self-defense.
Adaptation (change within the individual's lifetime)
This scientist believed that individuals evolved during their lifetime, and that these changes got passed onto offspring.
Lamarck
A population of brown bears gets fragmented into two separate regions. Then, a wildlife corridor is built so the two populations can interact and reproduce. Which population will be more genetically diverse - before or after?
After - a greater population means more genetic diversity.
For wild populations, there is a _________ between desirable survival-enhancing features and energy. For Holly Plants to grow spiky leaves, or snakes to produce venom, or animals to grow larger muscles, it "costs" energy and proteins and other macromolecules.
Tradeoff
Mr. C jumps into a cold pool. He gets very cold, then the water starts feeling comfortable.
Adaptation
This scientist believed that populations changed over time due to some traits being more advantageous for survival, and that these traits slowly became more common in populations over long periods of time.
Darwin
Name two selection pressures that humans 10,000 years ago faced.
Examples: predation, disease, warring with other tribes, access to food/water.
Elephants can give birth at about 15 years old. Bacteria, like E. Coli, can replicate in about 20 minutes. Which species will evolve faster?
Bacteria - shorter generations means the population can change more quickly
Some dinosaurs used to have sharp teeth for hunting. Their descendants, modern songbirds, now have beaks with no teeth for catching insects and breaking shells of nuts and seeds.
Evolution
Give an example of a piece of evidence that could cause the Theory of Evolution by Natural Selection to be downgraded to a hypothesis.
Examples: Finding fossils with limb bones of species that lived before these structures evolved.
Animals changing during their lifetimes and passing those changes on to offspring.
Grass doesn't die when it gets walked on. Other plants can die from this. Give an explanation for this.
Examples: humans artificially selected grasses that are resilient to being trampled.
Grass species evolved over time to survive better when disturbed.