Predicting Human Influence on a Watershed
How could the dam affect the resources of the local
watershed? Check all that apply.
A farming community is experiencing an extended
drought. Due to this, the community is low on water. The
local and state governments decide to build a dam on a
local river. One of the benefits for the farmers is that the
dam will create a reservoir, which the farmers can use to
irrigate their crops.
Fish would not be able to migrate up the river to
reproduce
Sediment carried by the flowing river would get
trapped.
There would be more space for forest growth.
The number of habitats for local wildlife would
increase
Birds that depend on fish may go hungry.
Awnser : fish would not be able to migrate up the river to reproduce
Sediment carried by the flowing river Would get trapped
Birds that depend on fish may go hungry.

when it's short and dry.

1) gene flow

- it is described as the transfer of genes from one population to another population so that frequency of gene is increased.

-a zebra migrates to join a different herd of zebras.

2) natural selection

- a mechanism of evolutionary change in which individuals with advantageous traits survive and reproduce whereas the others ( those that can not adapt) eliminate from the population.

-competition for sunlight leads to taller trees.

3) mutation

- permanent change in the nucleotide sequence of dna ( genetic material) that could have harmful or useful consequences.

-the dna of a snake changes to make its venom stronger.

4) genetic drift - it is a random phenomenon ( that occurs by chance such as fire) that results in change in the gene frequency in a small population.    

-a grassfire randomly sweeps through a population of buffalo and kills most of the animals.

explanation: