The Dodo's stepping stones the same as Phelsuma?
01/07/03 12:00 Filed in: Biogeography
The dodo was a flightless bird native to the island of Mauritius in the Indian Ocean. DNA from the extinct bird has revealed its place in the pigeon family tree, and suggests how it came to end up on its home, and graveyard, the island of Mauritius.
The dodo was a flightless bird native to the island of Mauritius in the Indian Ocean. DNA from the extinct bird has revealed its place in the pigeon family tree, and suggests how it came to end up on its home, and graveyard, the island of Mauritius.
The dodo's closest relative is also extinct, the solitaire pigeon (Pezophaps solitaria), which was also large and flightless and lived on Rodrigues Island, 550 kilometres east of Mauritius. It died out in about 1765, a century after the dodo (Raphus cucullatus).
Studies indicate that the proto-dodo/solitaire and the ancestor of the genus Caloenas ,the closest relative of the Dodo, diverged in the mid to late Eocene, around 43 Ma, whereas the dodo and the solitaire separated in the late Oligocene, about 26 Ma. The latter date is biogeographically interesting as it is considerably older than the islands of Mauritius and Rodrigues. Geological evidence suggests that Mauritius emerged in a series of volcanic events, the earliest of which occurred around 7 Ma, whereas Rodrigues did not emerge until 1.5 Ma. Therefore, it seems highly unlikely that the large genetic distance between the dodo and the solitaire resulted from isolation on the two islands.
Drilling projects have established that ridges surrounding the Mascarene Plateau were above sea level in the late Oligocene and have subsided slowly thereafter. The similarity between the timing of the dodo/solitaire divergence and the first geological evidence of land in the Mascarene island chain is striking and suggests that island steppingstones may have been used before the two species eventually found their way to Mauritius and Rodrigues. The solitaire and dodo reached their new homes by air, later evolving flightlessness independently.
Recent studies suggest that the solitaire of Réunion (Threskiornis solitarius) was apparently a flightless ibis closely related to the Sacred Ibis of Africa, though early travellers who reported the "solitaire" did not mention an ibis at all.
The dodo's closest relative is also extinct, the solitaire pigeon (Pezophaps solitaria), which was also large and flightless and lived on Rodrigues Island, 550 kilometres east of Mauritius. It died out in about 1765, a century after the dodo (Raphus cucullatus).
Studies indicate that the proto-dodo/solitaire and the ancestor of the genus Caloenas ,the closest relative of the Dodo, diverged in the mid to late Eocene, around 43 Ma, whereas the dodo and the solitaire separated in the late Oligocene, about 26 Ma. The latter date is biogeographically interesting as it is considerably older than the islands of Mauritius and Rodrigues. Geological evidence suggests that Mauritius emerged in a series of volcanic events, the earliest of which occurred around 7 Ma, whereas Rodrigues did not emerge until 1.5 Ma. Therefore, it seems highly unlikely that the large genetic distance between the dodo and the solitaire resulted from isolation on the two islands.
Drilling projects have established that ridges surrounding the Mascarene Plateau were above sea level in the late Oligocene and have subsided slowly thereafter. The similarity between the timing of the dodo/solitaire divergence and the first geological evidence of land in the Mascarene island chain is striking and suggests that island steppingstones may have been used before the two species eventually found their way to Mauritius and Rodrigues. The solitaire and dodo reached their new homes by air, later evolving flightlessness independently.
Recent studies suggest that the solitaire of Réunion (Threskiornis solitarius) was apparently a flightless ibis closely related to the Sacred Ibis of Africa, though early travellers who reported the "solitaire" did not mention an ibis at all.