Now, to examine our fishy and “slimy” friends. The obvious first choice from the fish lot is the flying fish. The flying fishes are gliding planktonivores who exit the water to escape predation, one of the major advantages of flight (the other usually being the ability to catch flying or gliding prey). Both the pectoral and pelvic fins are used in “flight” which allows for great surface area for the air to work on and also reduces the need for huge muscles as seen in some of the other fishes to use the gliding behavior. Glides can reach 60 km/h and last for 30 to 50 meters in distance. Flying fish predators might also develop gliding and flight as a means of catching the newly flying Exocoetids (flying fishes are members of Exocoetidae). Two issues with flying fish becoming true fliers: their pelvic muscles may be inadequate and their current plankton diet would hold them back, requiring a change in food.
Unusual this may sound, I think sharks have the possibilities to becoming either gliding or flying predators. From my knowledge, some of the larger sharks, specifically the great white shark, will “leap” out of the water with thrust in order to capture prey such as seals. I believe that smaller sharps would have the capability to take after this example and maintain short flights out of the water in order to catch fish prey (perhaps flying fish?).
Freshwater hatchetfish have the unusual tendency to fly. These are technically the only fish to use powered flight which makes them good candidates for what is referred to as true flight. This ability is granted by the hatchetfish’s large sternal region and large pectoral fins. Flight has both of the major advantages for the hatchetfish: it allows an escape from aquatic predators and allows for the hatchetfish to catch flying insects. For the Arthropod Era project, I have an idea for descendants of hatchetfish that are slightly larger and have improved the flight behavior by a large extent. To help extend flights, it has air sacs that act like both lungs and “flotation devices”.
I promised to write about flying amphibians but after some thought I don’t think that flight would develop in amphibians, not even the gliding frogs. My main issue is that amphibians require moisture and only in damp, humid areas would this requirement be met. In a “revisit” to a Carboniferous-type time, the likelihood for flying amphibians would rise. I imagine “pterosaur” or “bat” frogs existing, nothing like birds or insects for sure.
Filed under: Evolution, Future Evolution | Tagged: evolution of flight, flying animals, flying fish, Future Evolution, gliding animals, hatchetfish
the idea of flying sharks is interesting but highly unlikely. while many fish have swim bladders, which lungfish have developed into a lung sharks have giant livers to keep them afloat. So it would be difficult for them to develop lungs or air sacks. Also their cartilaginous skeleton would make for a poor support system for anything out of the water let alone something that would have endure the rigors of flight. Most flying animals seen to have evolved from a small animal then gotten big, so a flying fish would probably evolve from a rather diminutive ancestor.