How does the length of the history of life help to explain the evolutionary events of single-celled organisms to complex multicellular organisms like mammals?

In an experiment examining the effects tai chi on arthritis pain, callahan (2010) selected a large sample of individuals with doctor-diagnosed arthritis. half of the participants immediately began a tai chi course and the other half (the control group) waited 8 weeks before beginning. at the end of 8 weeks, the individuals who had experienced tai chi had less arthritis pain that those who had not participated in the course.

Which best describes this behavior? it is beneficial only to the males that do not fertilize eggs. it is beneficial only to the female workers that are not fertilized. it is beneficial to each one of the individual colony members. it is beneficial to the whole species, but not to all of the individual members.

14) whenever diploid populations are in hardy-weinberg equilibrium at a particular locus a) the allele's frequency should not change from one generation to the next, but its representation in homozygous and heterozygous genotypes may change. b) natural selection, gene flow, and genetic drift are acting equally to change an allele's frequency. c) this means that, at this locus, two alleles are present in equal proportions. d) the population itself is not evolving, but individuals within the population may be evolving.