Mammalian biodiversity on Madagascar controlled by ocean currents

  title={Mammalian biodiversity on Madagascar controlled by ocean currents},
  author={Jason R. Ali and Matthew Huber},
  • J. Ali, M. Huber
  • Published 4 February 2010
  • Environmental Science, Geography
  • Nature
Madagascar hosts one of the world’s most unusual, endemic, diverse and threatened concentrations of fauna. To explain its unique, imbalanced biological diversity, G. G. Simpson proposed the ‘sweepstakes hypothesis’, according to which the ancestors of Madagascar’s present-day mammal stock rafted there from Africa. This is an important hypothesis in biogeography and evolutionary theory for how animals colonize new frontiers, but its validity is questioned. Studies suggest that currents were… 
Spatial and temporal arrival patterns of Madagascar's vertebrate fauna explained by distance, ocean currents, and ancestor type
Oligate rafters show a decrease in probability of successful transoceanic dispersal from the Paleocene onward, reaching the lowest levels after the mid-Miocene, consistent with a paleoceanographic model that predicts Early Cenozoic surface currents periodically conducive to rafting or swimming from Africa.
Phylogeography of Myotis, Miniopterus and Emballonura bats from the Comoros and Madagascar
Using genetic markers, biogeographic origins, dispersal and diversification patterns of bats endemic to Madagascar and the Comoro islands are reconstructed and insight is given on when and how diversification was initiated in these western Indian Ocean bats.
The biogeographic origin of a radiation of trees in Madagascar: implications for the assembly of a tropical forest biome
The analyses support a late Miocene origin for Malagasy Canarium, probably by long distance dispersal from Southeast Asia, and postulate that the relatively recent establishment and radiation of Canarium in Madagascar may have been facilitated by the highly stochastic climates associated with these forest ecosystems.
Large-scale phylogeny of chameleons suggests African origins and Eocene diversification
It is suggested that contraction and fragmentation of the Pan-African forest coupled to an increase in open habitats (savannah, grassland, heathland), since the Oligocene played a key role in diversification of this group through vicariance.
Biogeography and the legacy of Alfred Russel
Biogeography is the study of life on Earth – what kinds exist, what they look like and where they are found. Starting with the Age of Discovery in the 15th century it became clear to early explorers
Biogeographic mechanisms involved in the colonization of Madagascar by African vertebrates: Rifting, rafting and runways
For 80 years, popular opinion has held that most of Madagascar's terrestrial vertebrates arrived from Africa by transoceanic dispersal (i.e. rafting or swimming). We reviewed this proposition,
Biogeography and the legacy of Alfred Russel Wallace
Biogeography is at the heart of nearly every major evolutionary event ever recorded in the history of the Earth and it is nearly impossible to understand those events without its appreciation.
How marine currents influenced the widespread natural overseas dispersal of reptiles in the Western Indian Ocean region
In a recent contribution to this journal, Wilmé et al. (2016) proposed that the giant tortoises of the islands of the Western Indian Ocean (WIO: Aldabra, the Mascarenes, and the Granitic Seychelles)
Two New Species of Mouse Lemurs (Cheirogaleidae: Microcebus) from Eastern Madagascar
A recent genetic analysis of mtDNA and nDNA sequence data in Malagasy mouse lemurs revealed the existence of several novel mtDNA clades based on new field sampling, and confirmed their evolutionary divergence from other mouse lemur clades, formally describing them as new species.


Historical Biogeography of the Strepsirhine Primates of Madagascar
  • I. Tattersall
  • Environmental Science, Geography
    Folia Primatologica
  • 2006
The palaeogeographic evidence for potential land bridge or ‘stepping-stone’ connections with adjacent continents from the Mesozoic through the Cenozoic is examined, and the fossil records and phylogenies of each of Madagascar's mammalian groups are reviewed in an attempt to estimate the minimum number of crossings necessary to produce the island’s current faunal composition.
Has Vicariance or Dispersal Been the Predominant Biogeographic Force in Madagascar? Only Time Will Tell
It is concluded that most of the present-day biota of Madagascar is comprised of the descendents of Cenozoic dispersers, predominantly with African origins.
Reconciling the Origins of Africa, India and Madagascar with Vertebrate Dispersal Scenarios
Most biogeographic explanations of these groups rely on Simpson’s model of sweepstakes dispersal, but there are significant problems in applying the model to migrations from Africa to Madagascar, although its application is not so intractable between India and Madagascar.
Natural change and human impact in Madagascar
A miniature continent long isolated from the African mainland, the island of Madagascar evolved a biota that remains one of the most varied of any environment in the world. Following the arrival of
Origin of Madagascar's extant fauna: A perspective from amphibians, reptiles and other non‐flying vertebrates
Analysis of phylogenetic patterns of some taxa provides indications for a scenario in which the ancestors of the Malagasy clades first arrived by transmarine dispersal from Africa at theMalagasy west coast, and in a second step a subset of them underwent species‐rich radiations into the rainforests.
Current available geologic and paleontologic data are most consistent with the Africa-first model, suggesting that Africa was the first of the major Gondwanan landmasses to be fully isolated prior to the Albian/Cenomanian boundary, and that its terrestrial vertebrate faunas became progressively more provincial during the Cretaceous, while those on other Gondwana landmassed remained relatively cosmopolitan until the later stages of the Late Cret Jurassic.
Asynchronous colonization of Madagascar by the four endemic clades of primates, tenrecs, carnivores, and rodents as inferred from nuclear genes.
A simultaneous reconstruction of phylogeny and age of the four radiations based on a 3.5-kb data set from three nuclear genes supports each as a monophyletic clade, sister to African taxa, and thereby identifies four events of colonization out of Africa.
Single origin of Malagasy Carnivora from an African ancestor
A multi-gene phylogenetic analysis is used to show that Malagasy carnivorans are monophyletic and thus the product of a single colonization of Madagascar by an African ancestor, and that a single event cannot explain the presence of both groups in Madagascar.
Is a new paradigm emerging for oceanic island biogeography?
Although a new general model of oceanic island biogeography has not yet been proposed, in this brief overview six hypotheses are presented that summarize aspects of the emerging paradigm and identify, testing, and seeking means of synthesizing these and other emerging hypotheses may allow a new conceptual paradigm to emerge.