prefer the inclusive fitness framework, but for humans we believe that both individual and group level approaches are essential. The likely reason for why is that many or most group traits originated in small, hunter-gatherergroups. Cenozoic: The era of geologic time from 65 mya to the present, a time when the modern continents essay on abdul kalam in telugu formed and modern animals and plants evolved. Among other issues, Smith is interested in the role of ecological gradients in speciation and maintaining species diversity. Cell size varies, but most cells are microscopic. Ewald, Paul: Professor of biology at Amherst College, specializing in hummingbird and flower coevolution and the evolution of infectious diseases. On culture and human nature, for perspectives that are of special relevance, see Pinker's paper on our "cognitive niche" i which, not least, deals with the problem of how natural selection came to endow our species with adaptations that enable us to perform cognitive feats. Then I finally went back to Mary Jane West-Eberhard's seminal work on social selection and found what I was looking for. Aperture: Of a camera, the adjustable opening through which light passes to reach the film.
shared intentionality, norms, institutions, punishment, gossip that conclusions appropriate for other animals may not apply. . Also, there is interpretive choice in whether one considers the functional phenotype as "really" existing at the individual level (which it must to initiate the feedback pathway or as "really" existing at the group level (which it must to complete the feedback pathwayeventually, multiplying gene. These are impressive to a human observer, but they are not what selection, literally interpreted, brings about. When it comes to answering the central question originally posed by Darwin, there is no alternative to group selection. This usage is frowned upon by many evolutionary biologists, but is established in much of the molecular literature.) homozygote: An individual having two copies of the same at a genetic. They gave rise to crocodiles, dinosaurs, and pterosaurs. Immutability: The ability to withstand change. The first big problem with group selection is that the term itself sows so much confusion. We can thus admit the complex division of labor and altruism in such eusocial species as termites and honeybees, but we must deny altruism in the case of humans, who cooperate widely with non-relatives. one point of agreement between group- and gene-selectionists is (or ought to be) that apart from kin selection, "traits cannot evolve that cause an average net decrease in individual fitness." So are there partitionings of fitness that involve costly self-sacrifice but that do add. The evolution of human behavior: Primate models.