Evolution Flashcards
What is Speciation
The formation of new species
What is micro evolution
Changes in allele frequency for a trait in a population
What is a species
Organisms capable of breeding freely with each other under natural conditions
What is reproductive isolating mechanisms
Any behavioural, structural or biochemical trait that prevents individuals of a species from reproducing
What are the types of natural selection?
Regular bell curve, stabilizing selection (skinny), directional selection (shifted bell curve), disruptive selection (two boobs), sexual selection
What is sexual selection?
Favouring a trait that improves mating success, can lead to dismorphism (male and female differences
What is regular bell curve selection?
In the absence of selection many traits exhibits a classic bell shaped curve, number of extremes are low
What is stabilizing selection?
Most common phenotype is favoured, intermediate phenotypes are favoured as population increases
What is directional selection ?
One extreme of the trait distribution experiences selection against it, population distribution trait shifts to other extreme
What is disruptive selection?
Selective pressure acts against individuals in the middle of the trust distribution. Results in bimodal curve where two extremes make their own curves.
What are the theories of why dogs became domesticated ?
- Stolen as pups
- Chose to be domesticated for better survival chances
What is the connection to tameness and different phenotype traits? Ex. Patchy costs, floppy ears
Adrenaline is connected to other hormones that control physical traits, tameness creates decreased levels of adrenaline.
What parts of DNA are theorized to be in the evolutionary process?
Regulatory DNA
What are the behavioural steps in the hunting process
Search, eyestalk, chase, grab bite, kill bite
Why is inbreeding a issue?
They are more vulnerable to genetic issues because the genetic pool is small
Does evolution describe the origin of life on earth?
No, it describes how species have adapted and evolved over time
Can individual organisms evolve during their lifetime ?
No, evolution happens over generations
Are natural selection and evolution the same thing?
No, natural selection is a theory for why evolution occurs
How old is the earth?
4.6 billion years old
Define evolution
Any change in the heritage traits within a population over generations
Define natural selection
A natural mechanism that selects traits that are most beneficial to a certain organism at a certain amount of time
How does natural selection work?
- Variation in between individuals is passed on
- every generation produces more offspring then can survive
3.there is a struggle for survival - survival depends on competition in species
5.organisms favourable variations survive and pass on genes
