Life history characteristics and survivorship patterns within a species are pre-set but may be changed according to the changes in environmental conditions needed for growth and reproduction. Allocation of energy to reproduction or other processes varies according to food availability, temperature, rainfall, etc.
Abundant resource availability favors the production of a large number of smaller offspring while limited resources make a population to produce a small number of larger progeny to increase the survival rate.
Example: Clutch size in birds is adjusted to obtain the maximum survival of progeny.
oceanic acidification is occurring, which results in shelled creatures, clams, lobster, to have weaker shells as a defense. the shells break easily and are too weak to protect the organisms inside, unable to properly calcify their shells leaves them vulnerable to preditors...