IBIS - Conférence «The tale of two fish: intraspecific variation, evolutionary cascades, and secondary contact»

Human  activity  has  profoundly  shaped  many  aquatic  ecosystems.  Incoastal  ecosystems  across eastern   North   America   dams   have   blocked   the   migration   of   anadromous   alewife,Alosa pseudoharengus, and created numerous landlocked populations. Alewife is an important species across  eastern  North  America.  The  anadromous  formmoves  between  marine  and  freshwater ecosystems  and  is  an  important  resource  for  communities  and  coastal  predators,  a  species  of conservation concern, and the target of considerable conservation and management activity. The landlocked  form  is  resident  in  freshwater  and  is  both  an  archetypal  keystone  species  and  an invasivespecies responsible for major changes in food web structure in lakes across eastern North America. Isolation of landlocked populations caused them to diverge from anadromous ancestors throughan  eco-evolutionary  feedback.  The  resulting  morphological  and  behavioral  differences between  landlocked  and  anadromous  alewifeinitiated  a  cascade  of  ecological  and  evolutionary changes that propagated through lake food webs. Now management activities designed to provide anadromous alewife access to historic spawning grounds are allowing anadromous and landlocked alewife  populations  to  come  back  into  contact  for  the  first  time  in  centuries.  Thisnatural experiment is an opportunity to understand the ecological and evolutionary dynamics of secondary contact from the initiation of contact. The results highlight the importance of intraspecific variation and  of  simultaneously  considering  ecological  and  evolutionary  processes  for  understand  the response of aquatic ecosystems toenvironmental change.

Conférencier: David M. Post, Professor of Ecology and Evolutionary Biology, Yale University

Hôte: Louis Bernatchez

Admission:
Inscription requise avant le mercredi 27 mars, 10h00

Lunch et breuvages seront offerts