(fill in the blank) word bank: radiation, accumulate, genetic drift, DNA

1: Helpful variations may in a population, while unfavorable ones may disappear.
2: , a mechanism of evolution, is a random, directionless process.
3: Mutations can occur when an organism is exposed to
4: Mutations may be the result of damage to a cell's

(write the answer)

#1: How do environmental factors contribute to evolution?
#2: How could 2 species, that compete for the same resources, affect each others' evolution?