What is the fitness of an organism?
A. The environment the organism lives in
B. The number of resources an organism uses
C. The total population of a species
D. The ability to survive and reproduce

What claim did thorne make? what evidence supported his claim?

Parasitism could be considered a form of which of these types of relationships? -mutualism -commensalism -predator-prey -mimicry

The table shows dates and appearance of index fossils. which rock layers can be dated most precisely? a) a layer containing both a fossil 4 and a fossil 3 b) a layer containing both a fossil 2 and a fossil 3 c) a layer containing both a fossil 1 and a fossil 4 d) a layer containing both a fossil 1 and a fossil 2