among members of kingdom animalia external fertilization is commonly observed in
External fertilization External fertilization is a male organism’s sperm fertilizing a female organism’s egg outside of the female’s body.[1] Internal fertilization, on the other hand, is the occurrence of internal insemination as the mode of combining sperm and egg.[2] External fertilization occurs in water or a moist area because it gives the sperm external mobility to get to the egg.[3] While in the water, the sperm and ova can shed simultaneously to fertilize the egg.[3] The release of eggs and sperm into the water is known as spawning.[4] When females spawn, they release a batch of eggs into a spot of their choice or just into the water, as in bottom dwelling or sessile species and all of the males start to release sperm that are in close proximity.[4] Within vertebrates, it is the amphibians and fish that use external fertilization.[5] When it comes to invertebrates, most are benthic, sessile, or benthic sessile combined animals such as coral, sea anemones, and tube dwelling polychaetes.[3] The benthic zone is the lowest level of the ocean where organisms called benthos reside.[6] An organism that is sessile does not have the ability to move or be mobile.[7] Benthic marine plants such as algae also go through external fertilization to reproduce.[3] Overall, environmental factors and the timing have a heavy influence over the success of external fertilization.In external fertilization some of the eggs laid by the animals gets wasted due to huge rainfall, floods etc.