W.D. Hamilton (1936-2000) Kin selection theory

Kin Selection Camponotus hyatti; Alex Wild

Kin Selection & Hamilton’s Rule Altruism is favored when: rB - C > 0 r = relatedness between altruist and recipient B = fitness benefit to recipient C = fitness cost to the altruist

Theory of Endosymbiosis

Volvox    Each little dot you see is a tiny green algae with two flagella. With this the individual organisms propel themselves. They do this in a coordinated manner so that the entire colony can move in one direction. To see Volvox in locomotion is simply breathtaking. This image shows a colony with one large daughter colony. These develop from one one cell inside the sphere. Inside the daughter colony the third generation is already beginning to develop. As well as asexuality Volvox also uses sexual reproduction. The dark spheres are egg-cells. They are fertilized by small packages of sperm. The species depicted is Volvox aureus . It can be up to one millimetre or more in size. It can be found in clear water when the temperatures are not too low. The end of summer is the right time for a good catch with a plankton net.