Which of the following statements about algal blooms is true? A. Algal blooms are caused by fish
B. Algal blooms can only happen naturally
C. Algal blooms are always human caused
D. Algal blooms are sometimes caused by natural occurrence and sometimes the result of human activities

According to the theory of punctuated equilibrium, at what rate does speciation occur? species change depending on the rate of natural selection. after periods of stasis, new species evolve relatively rapidly. species change slowly and eventually form new species. some species change quickly and others change slowly to balance the overall rate.

Classify the structures as homologous or analogous, depending on their structure and function.

Which of the following is not a potential result of deforestation?