speciation.

Question 1

What causes selectional pressures?

Answer 1

= predation
= disease
= competition]
= organisms that give them selective advantages are more likleu to surivie,produce offspring and pass down these advantegous alleles, change in allele frequency, evolutuon

Question 1

Why is there a wide range of variation in the in the phenotype?

Answer 1

= due to environmental and genetic factors
= genetoc variation is caused by mutation, meiosis, random fusion of gametes

Question 2

What is disruptive selection?

Answer 2

= bith extreme traits are favoured in the environment
= survive and pass down alleles
= allele frequency changes, more individuals posses, the alele extreme traut, middling trait becomes less,

Question 3

What is specitation?

Answer 3

= creation of a new species
= one original population of the same species becomes reproductivley isolated, cannot breed together, two populations pf the same spec ues
= accumulation of differences in gene pool, to the extent they cannot interbreed together, to produce fertile offspring

Question 4

What is genetic drift?

Answer 4

= change in allele frequency over generations in a population (evolution)
= always be genetic drift between generations, substantial genetuc drift results in evolution
= the smaller the population, the bigger impact allele frequency changes have- evoluton tends to occur in smaller populations