- ABOUT PENSOFT
- Dr. Malika Virah-Sawmy
- Biogeography and Ecology in Madagascar | NHBS Academic & Professional Books
- Biogeography and Ecology in Madagascar
- Nocturnal Species Research Project
Madagascar has made the news lately because of a military-backed coup, which has threatened conservation efforts. Criminal groups have taken advantage of the political turmoil to illegally log rare trees in Madagascar's dwindling forests, and the future of the former president's plans to massively expand the island's conservation areas now seem uncertain.
Where's the evolution? Why is Madagascar home to so many unique plants and animals? Because the island's geography, geology, and climate have provided opportunities for species to evolve and diversify in isolation. Its species are a mix of those that have been living and evolving there for many tens of millions of years and those that arrived more recently and subsequently diversified. Understanding where all of Madagascar's species came from i. One hundred and seventy million years ago, Madagascar was landlocked in the middle of the supercontinent Gondwana, sandwiched between land that would eventually become South America and Africa and land that would eventually become India, Australia, and Antarctica.
Through movements of the Earth's crust, Madagascar, along with India, first split from Africa and South America and then from Australia and Antarctica, and started heading north. Madagascar has been on its own for the past 88 million years. Under the marine dispersal scenario, a single fruiting branch possibly on a natural floating island or tree raft would be sufficient for male and female plants to become established in close proximity. Westward-moving monsoon pathways originated prior to the inferred movement of Canarium to Madagascar [ 5 ], as did contemporary warm westward moving currents [ 10 , 11 ].
While bird LDD cannot be completely dismissed, we interpret the available evidence as more strongly supporting marine dispersal from the IAA for Malagasy Canarium. An African origin of Malagasy Canarium would be feasible only under a scenario in which Canarium experienced middle to late Miocene extinctions in mainland Africa, a geologic era when tropical forests contracted with the expansion of the C4 grasslands [ 67 ] and tropical forest biodiversity was presumably lost.
It is conceivable that a once species-rich clade of African Canarium dispersed to Madagascar, but that subsequent extinctions left only a single African species, C. We note, however, that marine currents during the Miocene were largely unsuitable for marine or animal-mediated dispersal from Africa to Madagascar [ 7 ]. In any case, in the absence of fossils such speculations on an African origin are difficult to evaluate, and we favor dispersal from the IAA as the best interpretation of present molecular phylogenetic and morphological evidence, which unequivocally links Malagasy Canarium directly with Southeast Asian taxa.
How can the success of such a late-arriving lineage be explained? This climatic variability causes unpredictable patterns in floral phenology and has been hypothesized to play a significant role in shaping the evolutionary trajectory of faunal diversity on the island, including unusual life-history patterns, gigantism, and the paucity of mammalian clades [ 5 ]. In contrast, little attention has been paid to the impact of a hyper-variable climate on the evolution of plant communities on the island.
- Signs in Use: An Introduction to Semiotics?
- Biogeography and Ecology in Madagascar - Google книги?
- Security of Radioactive Sources Proceedings of an International Conference Held in Vienna, Austria, 10-13 March 2003;
Such a scenario has been invoked to explain adaptive radiations in other areas with unstable climatic regimes [ 70 ], and it would help to reconcile our findings with diversification patterns expected from evolutionary radiation into newly forming biomes [ 6 , 12 , 69 ]. If Malagasy plant communities have, in fact, experienced periodic high rates of lineage turnover, this could also help to explain aspects of the evolution of the associated animals, such as the limited number of frugivorous mammals [ 5 ].
Our findings help explain the origin of a previously undocumented radiation of rain forest trees in Madagascar. This finding is consistent with the observation that Malagasy rain forests experience hyper-variable climates. Under these circumstances, high rates of local extinction might provide an opportunity for late-arriving lineages to successfully colonize and radiate. The arrival of Canarium in Madagascar from the IAA highlights the potential significance of long distance dispersal in establishing pantropical distributions since the Oligocene.
Moreover, we suggest that the IAA may have served as a source area for multiple lineages now widespread in tropical forests, a topic deserving further investigation. Has vicariance or dispersal been the predominant biogeographic force in Madagascar? Only time will tell.
Annu Rev Ecol Evol Syst. Madagascar as a model region of species diversification. Trends Ecol Evol.
Spatio-temporal history of the endemic genera of Madagascar. Bot J Linn Soc. Wells N. Some hypotheses on the Mesozoic and Cenozoic paleoenvironmental history of Madagascar. The natural history of Madagascar. Chicago: University of Chicago Press; Evolution in the hypervariable environment of Madagascar. Biome shifting in plant evolution.
Ali JR, Huber M. Mammalian biodiversity on Madagascar controlled by ocean currents. Multiple colonization of Madagascar and Socotra by colubrid snakes: evidence from nuclear and mitochondrial gene phylogenies. Single origin of Malagasy Carnivora from an African ancestor. Effect of ocean gateways on the global ocean circulation in the late Oligocene and early Miocene.
Kennett JP. The Miocene ocean: paleoceanography and biogeography. Geol Soc Am. Immigration history controls diversification in experimental adaptive radiation. Burseraceae in Madagascar. Leenhouts P. Revision of the Burseraceae of the Malaysian area in the wider sense. Weeks A. Evolution of the pili nut genus Canarium L. Genet Resour Crop Evol.
Burseraceae, Flowering plants eudicots. New York: Springer; Insights into the historical construction of species-rich Mesoamerican seasonally dry tropical forests: the diversification of Bursera Burseraceae, Sapindales. New Phytol. Investigating processes of neotropical rain forest tree diversification by examining the evolution and historical biogeography of the Protieae Burseraceae.
- History of the Second World War, Part 28: Hit and Run: The Big Commando Raids begin.
- Armoured Fighting Vehicles of the World!
- Progress in Botany.
- Metadatas related.
- Biogeography and Ecology in Madagascar | SpringerLink!
- Manual of Insight.
Evol: Intl J Organic Evol. Edgar RC. Nucleic Acids Res. PartitionFinder: combined selection of partitioning schemes and substitution models for phylogenetic analyses. Mol Biol Evol. Gernhard T. The conditioned reconstructed process. J Theor Biol. The influence of model averaging on clade posteriors: An example using the triggerfishes Family Balistidae.
Dr. Malika Virah-Sawmy
Syst Biol. Relaxed phylogenetics and dating with confidence. PLoS Biol. Gregor H-J, Goth K. Stuttgart: Staatl. London clay flora. London: British Museum; Chandler MEJ. The lower Tertiary floras of southern England, vol. Fossils and seed plant phylogeny reanalyzed. Investigating processes of Neotropical rain forest tree diversification by examining the evolution and historical biogeography of the Protieae Burseraceae. Evol: Intl J Org Evol. Lieberman BS. Phylogenetic biogeography with and without the fossil record: gauging the effects of extinction and paleontological incompleteness.
Palaeogeogr Palaeoclimatol Palaeoecol. Treating fossils as terminal taxa in divergence time estimation reveals ancient vicariance patterns in the palpimanoid spiders. Syst Bio. The impact of shifts in marine biodiversity hotspots on patterns of range evolution: evidence from the Holocentridae squirrelfishes and soldierfishes. Biodiversity hotspots, evolution and coral reef biogeography. Yang Z. Fair-balance paradox, star-tree paradox, and Bayesian phylogenetics.
PhyNOIR: An algorithmic approach to phylogenetic noise isolation and reduction based on phylogenetic informativeness. BMC Evol. Stamatakis A.
Biogeography and Ecology in Madagascar | NHBS Academic & Professional Books
Bayes or bootstrap? A simulation study comparing the performance of Bayesian Markov chain Monte Carlo sampling and bootstrapping in assessing phylogenetic confidence. Webb CO, Ree R. Historical biogeography inference in Malesia. Matzke NJ.
Biogeography and Ecology in Madagascar
Model selection in historical biogeography reveals that founder-event speciation is a crucial process in island clades. A likelihood framework for inferring the evolution of geographic range on phylogenetic trees. Maximum likelihood inference of geographic range evolution by dispersal, local extinction, and cladogenesis. Bayesian analysis of biogeography when the number of areas is large. Mol Phylogenet Evol. Crame JA. Taxonomic diversity gradients through geological time.
Divers Distrib. Also try the list of participants. IB is on Twitter! Use islandbiology for posts about the conference. Detailed program online with links to abstracts of oral presentations! Registration deadline: Jul y 1st Important dates. Book your room at the international student residence before June, 15th Login Lost password? Create account. Main menu. Detailed program. Call for symposia closed. Call for workshops closed. Guidelines for authors.
Fees and Payment. Register closed. Mid conference.
Nocturnal Species Research Project
Post conference. Conference village. Find your way.