Because migration and and other seasonal movements can affect the possibility of finding a mate, stresses, that could affect offspring survival(can vary with season), and also availability of thing that are available for the offspring.
Answer:
skeletal system is a bone that we are having in all human bodies like skeletal in our head it protects our brain. like that the skeletal system defines
The runner is most likely dehydrated, not enough sleep, or heat stroke
The addition of acetyl groups to histones is associated with chromatin condensation and and higher levels of gene expression
