Why is food, water, clothing and shelter consider to be a measurement of need?

When organisms are classified ,they are given a two part name

Flock x flock y flock z total pieces of food eaten (from previous page) 147 93 60 food percentage* % % % simulated number of birds in flock for 3rd generation** * divide each flock's total pieces of food by 300, the total number of pieces of food eaten. ** multiply the food percentage for each flock by the total number of birds (30).

Can a trait be both polygenic and have multiple alleles? explain why or why not.