Sociobiologists, the most well known of whom is Edward O. Wilson, contend that there is a biological basis for the social behavior of animals, and they test their hypotheses through observation of animals in situations. Species studied have varied as widely as to encompass both termites and rhesus macaques. Sociobiologists further argue that students of human behavior cannot adequately account for the panoply of human nature through only such traditional variables as culture, ethnicity, and environment but must also include evolutionary processes. However, many scientists, notably Stephen Jay Gould and Richard Lewontin, have criticized this approach to the study of humans on a number of grounds: for example, that it is based on Eurocentric notions and that it is plagued by methodological problems. These detractors label it a pseudo-science because sociobiological theories are not falsifiable and thus, in this respect, are similar to alchemy or astrology.