While insects and similar types of organism strived to occupy land, the sea was teaming with life aiming to secure their long term survival. As a consequence of this, reproduction occurred and genetic variation increased. This results in the arrival of fish,
While insects and similar types of organism strived to occupy land, the sea was teaming with life aiming to secure their long term survival. As a consequence of this, reproduction occurred and genetic variation increased. This results in the arrival of fish, who were adapting to live in the largest ecosystem on earth, water.
There are over 20 000 species of fish, all of which have diversified over time to aptly occupy a particular habitat. Since aquatic environments vary greatly in regards to its characteristics, fish diversity also varies greatly.
Factor - Temperature
Depending on season, chronological point in time, depth of water and many other factors, temperature will affect how a fish species would occupy or even exist in an ecosystem. An example is some species being better suited to tropical warm waters while others occupy the polar regions of Earth in its present day
Factor - Saltwater / Freshwater
Fish have diversified to occupy saltwater and freshwater in the best way possible. This is further illustrated in the animal water regulation tutorial page. The main reason for this being a significant factor is the effect that salt has on osmoregulation, thus fish have underwent significant anatomical adaptations to occupy the respective environments
Factor - Biotic Relationships
Other species may represent competition, danger, a source of food or provide a symbiotic relationship. Nonetheless, all species are inevitably a factor, and this is indeed the same case for fish. Check out the producer / consum