ProjectA5
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Lemurs are living representative of one of the most primitive strata of primate evolution. They are represented by two distinct groups, the Lemurs and the Loris which split more than 37 Ma ago. Both share many primitive Primates characters but also a uniquely derived character, the tooth comb. This dental speciality is the result of the procumbent inclination of lower incisors and canines which become also peg-like, designing what is commonly called the tooth comb. Their modern geographic distribution is restricted to Madagascar for the Lemurs and to the old world tropics (Tropical Africa & Asia) for the Loris. Their fossil record is very scanty, only fossil Loris being known from the late Eocene to Pleistocene of Africa and from the Miocene of Indo-Pakistan. No fossil of Lemurs older than Holocene is presently known. Thus, the geographic origin of Malagasy Lemurs remains one of the most resistant biogeographic puzzles. Surprisingly, recent discoveries of Eocene Primates in Africa did not contribute to solve that problem. In addition, the peopling of Madagascar is not only restricted to that of Lemurs. Other endemic Madagascar mammals indicate that, according to our knowledge about the history of mammals, 4 or 5 successive waves of peopling occurred during the Tertiary, either from the Indian plate, from Africa or from both places! In order to gain a better understanding of the problem of geographic origin of Lemurs, we propose to address the problem using several distinct methods: | Lemurs are living representative of one of the most primitive strata of primate evolution. They are represented by two distinct groups, the Lemurs and the Loris which split more than 37 Ma ago. Both share many primitive Primates characters but also a uniquely derived character, the tooth comb. This dental speciality is the result of the procumbent inclination of lower incisors and canines which become also peg-like, designing what is commonly called the tooth comb. Their modern geographic distribution is restricted to Madagascar for the Lemurs and to the old world tropics (Tropical Africa & Asia) for the Loris. Their fossil record is very scanty, only fossil Loris being known from the late Eocene to Pleistocene of Africa and from the Miocene of Indo-Pakistan. No fossil of Lemurs older than Holocene is presently known. Thus, the geographic origin of Malagasy Lemurs remains one of the most resistant biogeographic puzzles. Surprisingly, recent discoveries of Eocene Primates in Africa did not contribute to solve that problem. In addition, the peopling of Madagascar is not only restricted to that of Lemurs. Other endemic Madagascar mammals indicate that, according to our knowledge about the history of mammals, 4 or 5 successive waves of peopling occurred during the Tertiary, either from the Indian plate, from Africa or from both places! In order to gain a better understanding of the problem of geographic origin of Lemurs, we propose to address the problem using several distinct methods: | ||
Revision as of 09:46, 6 July 2009
Project A5: A restudy of Madagascar-Africa breakup and evolution of Lemurs
French pi: J.J. Jaeger (with J. Dyment)
South African pi: J. Masters (with M. de Wit)
RSA Participants: Phd Student John Decker and students from Univ Fort Hare
Contents |
Background
Lemurs are living representative of one of the most primitive strata of primate evolution. They are represented by two distinct groups, the Lemurs and the Loris which split more than 37 Ma ago. Both share many primitive Primates characters but also a uniquely derived character, the tooth comb. This dental speciality is the result of the procumbent inclination of lower incisors and canines which become also peg-like, designing what is commonly called the tooth comb. Their modern geographic distribution is restricted to Madagascar for the Lemurs and to the old world tropics (Tropical Africa & Asia) for the Loris. Their fossil record is very scanty, only fossil Loris being known from the late Eocene to Pleistocene of Africa and from the Miocene of Indo-Pakistan. No fossil of Lemurs older than Holocene is presently known. Thus, the geographic origin of Malagasy Lemurs remains one of the most resistant biogeographic puzzles. Surprisingly, recent discoveries of Eocene Primates in Africa did not contribute to solve that problem. In addition, the peopling of Madagascar is not only restricted to that of Lemurs. Other endemic Madagascar mammals indicate that, according to our knowledge about the history of mammals, 4 or 5 successive waves of peopling occurred during the Tertiary, either from the Indian plate, from Africa or from both places! In order to gain a better understanding of the problem of geographic origin of Lemurs, we propose to address the problem using several distinct methods:
- Reinvestigating marine geophysical and DSDP data in the Mozambique Channel and vicinities, reassessing ancient and recent plate kinematics of this part of the Indian Ocean.
- Prospecting the Paleogene deposits of Madagascar.
- Prospecting the Paleogene deposits of South Africa and Mozambique.
