Evolution And Adaptations In Animals/parasites/plants Flashcards
What is natural selection?
The organisms that are better adapted to their environment will survive and reproduce.
What happens if a mutation has a survival advantage?
Then the organism will live to the breeding age, since there is a survival advantage the organism is able to reproduce.
What is evolution?
Is a change in the inherited characteristics in a population which happens over time through the process of natural selection. Which may result in the formation of a new species due to the change in characteristics.
How can a mutation lead to speciation?
The mutation carried will be passed on to the offspring, and over many generations the frequency of the mutations will increase in the population. Leading to the population that carries the mutation to become very different to the extent that they’re not going to be able to reproduce with members of the other population/species. (Mutations could also lead to speciation)
What is speciation?
Is a process that results in the formation of a new species
How does speciation occur?
Due to isolation (when populations of the same species become separated) and also due to natural selection (when the populations become seperated they try to adapt to the environment they are in so that they can survive and reproduce.)
What is The process of speciation?
1- Populations of the same species can become isolated from eachother due to the formation of a physical barrier (river, mountains)
2- The environment will be different on either side of this physical barrier (different climates or different food available)
3- natural selection will occur causing a different set of characteristics to become more common in the two isolated populations.
4- over many generations, members of the 2 populations will become very different to the extent that they’re not able to interbreed to produce fertile offspring.
5- 2 populations will have become separate species.
How is a fossil formed?
The organism will be buried in the sand.
The organism bones will not be decayed or not be eaten causing the bones to be imprinted in the sediment.
What is the theory of evolution?
It states how organisms have changed over time
Explain the process of natural selection- (in moths for example)
!A CHANGE IN A GENE OCCURS!
causing Variation to occur in a population due to a random mutation.
The organisms compete to survive
The mutation may have caused advantageous genes to aid survival such as a moth being dark colored to camouflage in the tree branch.
Surviving organisms reproduce and pass on their ADVENTAGOUS ALLELES.
The advantageous alleles that aids for survival will become more common in the population causing more moths to survive.
In which populations does natural selection occur in?
The populations which contain genetic variation
Explain how the king snake evolved to have a similar appearance to the coral snake (hint: “evolved” in a question means natural selection)
Variation- a change in a gene occurs causing genetic variation in the population of king snakes.
Competition- the king snakes compete for survival
Survival- the king snakes that look most similar to the coral snakes will survive.
Reproduction- the king snakes which survived will reproduce and pass on the alleles for the coral snake colour to the offsprings.
The alleles for the coral snake colour will be more common.
What can natural selection lead to?
Natural selection leads to the formation of a new species due to the process of speciation.
What does Charles Darwin’s theory state?
It states that members in a species show a range of variation due to difference in their genes.
Organisms with characteristics most suited to the environment will have a higher chance of survival, more chances to reproduce. Survival = reproduction
alleles that code for advantageous characteristics are therefore passed to offspring.
Over many generations, the advantageous characteristics are more common in the population causing the species to evolve.
Natural selection example for snails: how snails have a white shell from a black shell colour?
Variation occurs in the snail population due to a change in a gene causing a mutation.
Mutation causes a small number of snails to have a white shell.
The white shelled snails are more likely to survive longer since they’re better camouflaged so less likely to be seen/ eaten by predators.
Since the snails survive longer they get more opportunities to reproduce and so these advantageous alleles for the white shell are passed on to the offspring more than the black and grey shells since snails with white shells have a higher chance of survival.
Over many generations, the white shell allele becomes common in the population causing the species to evolve.
