Paleobiogeography: The relevance of fossils to biogeography

Paleobiogeography has advanced as a discipline owing to the increasing utilization of a phylogenetic approach to the study of biogeographic patterns. Coupled with this, there has been an increasing interdigitation of paleontology with molecular systematics because of the development of techniques to analyze ancient DNA and because of the use of sophisticated methods to utilize molecules to date evolutionary divergence events. One pervasive pattern emerging from several paleontological and molecular analyses of paleobiogeographic patterns is the recognition that repeated episodes of range expansion or geo-dispersal occur congruently in several different lineages, just as congruent patterns of vicariance also occur in independent lineages. The development of new analytical methods based on a modified version of Brooks Parsimony Analysis makes it possible to analyze both geo-dispersal and vicariance in a phylogenetic context, suggesting that biogeography as a discipline should focus on the analysis of a variety of congruent phenomena, not just vicariance. The important role that extinction plays in influencing apparent biogeographic patterns among modern and fossil groups suggests that this is another area ripe for new methodological developments

Evolutionary relationships and divergence times among the native rats of Australia

Background The genus Rattus is highly speciose and has a complex taxonomy that is not fully resolved. As shown previously there are two major groups within the genus, an Asian and an Australo-Papuan group. This study focuses on the Australo-Papuan group and particularly on the Australian rats. There are uncertainties regarding the number of species within the group and the relationships among them. We analysed 16 mitochondrial genomes, including seven novel genomes from six species, to help elucidate the evolutionary history of the Australian rats. We also demonstrate, from a larger dataset, the usefulness of short regions of the mitochondrial genome in identifying these rats at the species level. Results Analyses of 16 mitochondrial genomes representing species sampled from Australo-Papuan and Asian clades of Rattus indicate divergence of these two groups ~2.7 million years ago (Mya). Subsequent diversification of at least 4 lineages within the Australo-Papuan clade was rapid and occurred over the period from ~ 0.9-1.7 Mya, a finding that explains the difficulty in resolving some relationships within this clade. Phylogenetic analyses of our 126 taxon, but shorter sequence (1952 nucleotides long), Rattus database generally give well supported species clades. Conclusions Our whole mitochondrial genome analyses are concordant with a taxonomic division that places the native Australian rats into the Rattus fuscipes species group. We suggest the following order of divergence of the Australian species. R. fuscipes is the oldest lineage among the Australian rats and is not part of a New Guinean radiation. R. lutreolus is also within this Australian clade and shallower than R. tunneyi while the R. sordidus group is the shallowest lineage in the clade. The divergences within the R. sordidus and R. leucopus lineages occurring about half a million years ago support the hypotheses of more recent interchanges of rats between Australia and New Guinea. While problematic for inference of deeper divergences, we report that the analysis of shorter mitochondrial sequences is very useful for species identification in rats

iREDD hedges against avoided deforestation's unholy trinity of leakage, permanence and additionality

Workable financial mechanisms are essential to abate greenhouse gas emissions. Deforestation, which contributes a large proportion of total global emissions, must be avoided as an effective emissions-reduction tactic, and to alleviate biodiversity loss and poverty. However, incentives to reduce emissions from deforestation and forest degradation (REDD) have had mixed and suboptimal success because of opportunity costs and administrative and technical issues, in particular, leakage, permanence, and additionality. We show that these latter concepts can be ambiguous, potentially contrived and in some cases, generate perverse outcomes. Encumbering avoided-deforestation projects with these administrative shackles risks massive increases in global deforestation and a concomitant loss of biodiversity, ecosystem services and emissions-reduction opportunities. We offer a solution built on a proven insurance-based hedging principle, a concept we call iREDD, that could indirectly address specific technical and administrative challenges, whether real or contrived. Project-specific iREDD insurance policies and premiums would be negotiated upfront using a simple assessment of risk based on governance quality, the integrity of management plans, liquidity, monitoring and evaluation frameworks, and political acceptability. iREDD acts as both an incentive for prudent forest management given the seller's potential financial windfall if forests are diligently managed, and guarantees not to disenfranchise the buyer.Penny van Oosterzee; James Blignaut; Corey J. A. Bradsha

Resilience and Opportunity: regions and the roll-out of Australia's greenhouse gas abatement programs - a manual for Queensland's NRM regions

[Extract] Voluntary and compliance markets for forest carbon and other (emission avoidance and biosequestration) activities are growing internationally and across Australia. Queensland and its Natural Resource Management (NRM) regions have an opportunity to take a variety of actions to help guide these markets to secure multiple landscape benefits and to build landscape resilience in the face of climate change. As the national arrangements for offsets within Australia's Clean Energy Package (CEP) and emissions trading environment emerge, Queensland's regions can prepare themselves and their landholding communities to take advantage of these opportunities to deliver improved climate resilience in their regional landscapes