I'm pretty sure it's primary growth. I might not have studied this type of biology yet, but secondary growth would definitely not be the answer.<span />
They eat food, they drink water, they need vitamins either from the sun or soil to nourish themselves, they grow overtime, lastly but most importantly, they are affected by weather.
Variation becomes an advantage if neither of the individuals
is having detrimental traits. If neither of the individuals is having the
detrimental trait then that means that a bad gene is being introduced in the
population. Other times, variation is an advantage since it provides the population
with better traits and devices to use on their environment. This is crucial
since the environment changes over time.
A salmon can live out of water for 2 hours
