Professor Bell’s seminar on the effects of climate change on species was intriguing. It was presented both in scientific terms and after in common easily understood terms. In addition the seminar was easy to listen to as it mixed scientific evidence with humor.
Bell began his talk with an explanation of variation of global conditions, and suggestions on how change begins slowly but becomes more extreme in the future. Bell then describes the ways species may respond to such global changes. They may alter certain traits or adapt, wait until conditions return to what the species is compatible with (dormancy), or they may migrate or change their area of accessible habitat. If the species is unable to cope with these changes it will go extinct.
Finally the potential results of climate change are stated with regards to diversity complexity and evolutionary change. The main possible affects appear to be changes in community structure and species adaptations. Bell illustrates the potential adaptations of climate change using the example of an experiment with algae and their response to CO2 levels. The article Phenotypic consequences of 1,000 generations of selection at elevated CO2 in a green alga by Collins and Bell is related to this example.
Some of the final messages given by this seminar are the potential for species to adapt (which increases with more gradual change), and the possibility that for certain species, decline may reach a trough and return to normal through evolutionary rescue. However the speed of global changes is occurring at a faster rate than before.
Bell’s seminar had me reflect on several things, mostly concerning what the species changes might mean for our future world. Adaptation suggests a differing biological and ecological construct of the world as we know it. Migration and habitat change may have implications concerning loss of diversity in certain areas (where species can no longer return to relatively hostile conditions) or increase in diversity with immigration of foreign species (provided that the invaders do not out compete the natives). Dormancy would suggest a need for conditions to return to normal for us to recognize the world as we see today. The ability to forsee the effects of climate change are further complicated by the relationships between communites and the species within them; a potential positive mutation for species A may negatively impact species B with returning negative impacts for species A. The opposite may occur for a negative mutation.