Why would an individual survive and reproduce if it displays behaviour that has disadvantages or incurs costs itself? For example, a vampire bat donates a blood meal to another vampire bat even though there is no benefit to the donor. The donor has no guarantee that it would find food to sustain itself in the near future. This type of social behaviour is called altruism, when the donor is at a disadvantage or has a cost while the receiver benefits. In fact, it seems that there is a paradox over the evolution of this type of social behaviour since the helper experiences a cost to itself.
A vampire bat (courtesy of Wikimedia user Ltshears)
The idea of survival and selection of an individual was originally based on the theory of evolution put forth in the 19th century by Charles Darwin. After reading Darwin’s theory, an English scientist called Herbert Spencer developed the idea of survival of the fittest (Wee, Alvin 2013). This concept means that an individual that was better able to survive in their environment was the one that lived and passed on characteristics to his or her offspring (babies). With regard to altruism, it would then appear that if an altruist experienced costs, these disadvantages would make the altruist less likely to survive and reproduce. In fact, altruism is present in the world, and is important to the survival of groups, as explained in the following video (credits are given in the video).
[youtube]http://youtu.be/NKImdgs-Re0[/youtube]
In the video, there was an explanation of how shared genes are passed on by the group at the expense of the individual (Freeman, Scott 2008). This process is called kin selection. In order to investigate how kin selection and other variables affect the evolution of social behaviour, evolutionary biologist Dr. Florence Débarre and her research team developed a mathematical model (a representation based on mathematics) in this area. Recently, in March 2014, Joseph Burant, host of UBC Science Talk, interviewed Dr. Débarre.
Dr. Florence Débarre (courtesy of Florence Débarre via http://biosciences.exeter.ac.uk/staff/index.php?web_id=Florence_Debarre).
Dr. Débarre’s research paper agreed with findings from other researchers that altruism evolves if altruists interact more often with other altruists. Through this interaction and kin selection, social behaviours such as altruism evolve if the overall benefit is greater for the group than the cost of competing against this group. Although altruism seems to be a paradox to the survival and reproduction of an individual, altruism helps groups survive and thrive.
Reference:
Débarre, F. (2014). In Burant J. (Ed.), Personal interview via skype. Vancouver, B.C.:
Freeman, S. (2008). Kin selection. In B. Wilbur, A. Gilfillan, S. Winslow & B. Ruden (Eds.), Biological science: volume 2 (evolution, diversity, and ecology) (3rd ed., pp. 1168). San Francisco: Pearson Benjamin Cummings.
Wee, A. (2013). Herbert spencer (1820-1903). Retrieved 04/06, 2014, from http://www.victorianweb.org/philosophy/spencer/spencer.html
by Joseph Burant, Simeng Alexandra Cai, & Jason Leung
SCIE 300 – 211 (Group 1)
