Not sure if this is correct, can someone help me please?

5) these are organisms where the genetic material is not bound by a nucleus. they are usually unicellular.

Amale bird-of-paradise uses a dance to attract mates in which it flaps its tail feathers on the ground and jumps around a potential female mate. a different male bird-of-paradise does a similar dance but it jumps around the female in the opposite direction. the female bird is only attracted to one style of dance, in one direction. this is an example of speciation.

When analyzing tree rings, what do scientists assume a thin ring indicates?