the structural characteristis of many species such as sharks have changed little over time what evolutionary?

Question

factors might be affecting their stability?

Answer 1

Species that have been around for a very long time have successfully reproduced because they are very well adapted to their environment and their environment has not changed very much. Another factor is that the more specialized a species becomes, the more at risk the species is of extintion if the environment changes. Since, over geologic time, the earth's climate changes and areas that were swamps become deserts, etc, successful species have to be able to move or spread their offspring to areas where the environment is right for them.

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