A local birdwatcher who has been watching a certain species of birds around his community for decades suddenly discovers one of the birds in the population has red-tipped feathers. This was different from the usual green and brown tipped feathers. Part A.
What is responsible for causing the sudden appearance of a new gene in the bird species?
a. a mutation
b. an environmental
c. artificial selection
d. a physical injury to the wings

i think that is new experiments yield untrustworthy data and should be carefully considered, because you don't know what will happen with the experiments.

a symbiotic relationship with the mitochondria

the circled areas are referred to   as sunspots.   the sunspots are cooler than the   surrounding area.

sunspots are temporary phenomena on the photosphere of the sun that appear visibly as dark spots compared to surrounding regions. they correspond to concentrations of magnetic field flux that inhibit convection and result in reduced surface temperature compared to the surrounding photosphere.