26-08-2017, 09:45 AM
Evolution
The earliest known remains of fossil bats (50-60 million years ago) show that even in the early Eocene, bats resembled much what they do today. Long before human ancestors resembled apes, species of bats similar to the species of Microchiroptera (microbats) today were flying and the use of echolocation to chase insects!
Bats represent the only known example of flight in mammals. How this trait evolved, or where it is not true due to the lack of fossilized evidence. The "missing link" between mammals that do not fly and bats is still missing - and an important piece of the puzzle, without which it is impossible to know with certainty the ancestor of modern bats.
Scientists believe, however, that the Microchiroptera probably evolved from small mammals of slip of the order Insectivora. This order today includes small rodents like mammals that feed on insects such as shrews or moles. Scientists believe that these bats may have developed the ability to fly to escape predation, or to look for an increasingly abundant and diverse source of flying insects that were evolving at the same time.
The two bat suborders, the Microchiroptera (microbats) and Megachiroptera (megabats), seem to share many similarities that suggest a common ancestor and a similar evolution. While this is generally accepted theory, there are some significant differences between the two suborders that has led some scientists to suggest that Megachiroptera may have evolved differently from Microchiroptera.
Those who support this argument point to the lack of echolocation between the species of Megachiroptera, the difference in their pulp teeth and the shape of their heads as evidence. The first fossil record of Megachiroptera is only 35 million years ago (Oligocene). The teeth of these fruit bats are designed to crush the pulp and differ significantly from those of Microchiroptera insectivorous. It is generally accepted that the shape of the Megachiroptera teeth could not have evolved from the shape of the teeth found in Microchiroptera. The lack of echolocation among species of Megachiroptera also stimulates the question of how this adaptation evolved in one suborder, but not in the other.
Those scientists who believe that the Megachiroptera can not share an ancestor with the Microchiroptera suggest these larger bats and frugivorous that might have evolved from the Primates. This theory is certainly interesting in that it suggests that flight evolved among mammals not only once but twice that humans share a common ancestor with fruit bats!
These questions about the evolution of bats have not yet been answered. The skeletons of bats are fragile and often do not last long enough to fossilize. Therefore, it is difficult to know with certainty how micro- and mega-bats evolved. Today's scientists are still putting the picture together!
The earliest known remains of fossil bats (50-60 million years ago) show that even in the early Eocene, bats resembled much what they do today. Long before human ancestors resembled apes, species of bats similar to the species of Microchiroptera (microbats) today were flying and the use of echolocation to chase insects!
Bats represent the only known example of flight in mammals. How this trait evolved, or where it is not true due to the lack of fossilized evidence. The "missing link" between mammals that do not fly and bats is still missing - and an important piece of the puzzle, without which it is impossible to know with certainty the ancestor of modern bats.
Scientists believe, however, that the Microchiroptera probably evolved from small mammals of slip of the order Insectivora. This order today includes small rodents like mammals that feed on insects such as shrews or moles. Scientists believe that these bats may have developed the ability to fly to escape predation, or to look for an increasingly abundant and diverse source of flying insects that were evolving at the same time.
The two bat suborders, the Microchiroptera (microbats) and Megachiroptera (megabats), seem to share many similarities that suggest a common ancestor and a similar evolution. While this is generally accepted theory, there are some significant differences between the two suborders that has led some scientists to suggest that Megachiroptera may have evolved differently from Microchiroptera.
Those who support this argument point to the lack of echolocation between the species of Megachiroptera, the difference in their pulp teeth and the shape of their heads as evidence. The first fossil record of Megachiroptera is only 35 million years ago (Oligocene). The teeth of these fruit bats are designed to crush the pulp and differ significantly from those of Microchiroptera insectivorous. It is generally accepted that the shape of the Megachiroptera teeth could not have evolved from the shape of the teeth found in Microchiroptera. The lack of echolocation among species of Megachiroptera also stimulates the question of how this adaptation evolved in one suborder, but not in the other.
Those scientists who believe that the Megachiroptera can not share an ancestor with the Microchiroptera suggest these larger bats and frugivorous that might have evolved from the Primates. This theory is certainly interesting in that it suggests that flight evolved among mammals not only once but twice that humans share a common ancestor with fruit bats!
These questions about the evolution of bats have not yet been answered. The skeletons of bats are fragile and often do not last long enough to fossilize. Therefore, it is difficult to know with certainty how micro- and mega-bats evolved. Today's scientists are still putting the picture together!