Nonnative species are not always a negative factor, they become invasive species .

a.
as soon as they are introduced in an ecosystem
b.
as soon as they leave their original ecosystem
c.
when they start consuming the food meant for the native species
d.
when their presence become economically or environmentally damaging
e.
when they control other species

Ricardo notices that when he plays soccer in the rain, his ball does not seem to go as far after a kick. what is the best scientific question that ricardo could ask about this observation? is soccer better played in the rain or sun? how does rain affect the distance a soccer ball can travel? how does rain affect the speed of a soccer ball? is soccer affected by the rain?

Compare and contrast cladistics and phylogeny. what are their advantages and disadvantages? which is the most useful in understanding how an organism developed into its current form? which concept most strongly supports your opinion about the origin of any given organism?

Aheterozygous normal male marries a woman with a sickle cell anemia. give the genotypes and possible phenotypes of the offspring