Final answer:
A testable hypothesis when an ocean-going species is found in two far-apart locations is that speciation has occurred due to different environmental pressures. This can be tested through genetic analyses and studies of reproductive isolation. Examples of this hypothesis in action include differing behaviors and physical adaptations in geographically separated owl populations.
Step-by-step explanation:
When an ocean-going species is found in two geographically distant locations, one testable hypothesis is that the species has undergone speciation due to environmental variation. The distance could result in differential selective pressures that drive evolutionary changes in each geographically isolated population. This hypothesis draws on the principle that environmental factors like climate, available prey, and other organisms with which they interact differ significantly between two distant locations, leading to evolved differences in species within those ecosystems. This can be seen in examples like northern and southern populations of owls, where behavioral and physical adaptations may lead to speciation.
Conducting genetic analyses of individuals from both locations, observing mating behaviors, and studying dietary preferences can provide data to support or refute this hypothesis. Experiments can be designed to test for reproductive isolation between the two groups, which is considered a hallmark of speciation. This hypothesis assumes that there is limited or no gene flow between the two populations.