Theories On The Evolution of A Biphasic Life History
Marine larval dispersal is one of the most important topics in marine ecology today. Most marine invertebrates and many fishes have evolved a life cycle involving a demersal adult and a pelagic larval stage or pelagic eggs that have the capacity to be transported long distances. There are several theories behind why these organisms have evolved this biphasic life history:
- Larvae use a different food source than adults, which may decrease competition between life stages.
- Pelagic larvae have the potential to disperse long distances, colonize new territory, and move away from habitat that has become overcrowded or otherwise unsuitable.
- A long pelagic larval duration can help a species break its parasite cycles.
- Pelagic larvae avoid benthic predators.
Pelagic larval dispersal, however, is not without its risks. For example, while larvae do avoid benthic predators, they are exposed to a whole new suite of predators in the water column.
Read more about this topic: Marine Larval Ecology
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