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No endemic Madagascar animal with body mass >10 kg survived a relatively recent wave of extinction on the island. From morphological and isotopic analyses of skeletal “subfossil” remains we can reconstruct some of the biology and behavioral ecology of giant lemurs (primates; up to ∼160 kg) and other extraordinary Malagasy megafauna that survived into the past millennium. Yet, much about the evolutionary biology of these now-extinct species remains unknown, along with persistent phylogenetic uncertainty in some cases. Thankfully, despite the challenges of DNA preservation in tropical and subtropical environments, technical advances have enabled the recovery of ancient DNA from some Malagasy subfossil specimens. Here, we present a nuclear genome sequence (∼2× coverage) for one of the largest extinct lemurs, the koala lemur Megaladapis edwardsi (∼85 kg). To support the testing of key phylogenetic and evolutionary hypotheses, we also generated high-coverage nuclear genomes for two extant lemurs, Eulemur rufifrons and Lepilemur mustelinus , and we aligned these sequences with previously published genomes for three other extant lemurs and 47 nonlemur vertebrates. Our phylogenetic results confirm that Megaladapis is most closely related to the extant Lemuridae (typified in our analysis by E. rufifrons ) to the exclusion of L. mustelinus , which contradicts morphology-based phylogenies. Our evolutionary analyses identified significant convergent evolution between M. edwardsi and an extant folivore (a colobine monkey) and an herbivore (horse) in genes encoding proteins that function in plant toxin biodegradation and nutrient absorption. These results suggest that koala lemurs were highly adapted to a leaf-based diet, which may also explain their convergent craniodental morphology with the small-bodied folivore Lepilemur .
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This content will become publicly available on May 22, 2027
Mammal-infecting DNA viruses identified in lemurs and rodents in Madagascar mirror the evolutionary history of their hosts
Given that some DNA viruses have been found to exhibit virus–host co-evolution and establish lifelong infection, mammals with unique evolutionary histories in island ecosystems likely host exceptionally diverse viruses. Madagascar is inhabited by endemic non-human primate and rodent lineages interacting with expansive populations of introduced non-native rodents across the island. Using a viral metagenomic workflow on 189 oral swabs of lemurs and rodents in southeastern Madagascar, we characterized genomic sequences of DNA viruses in the familiesAdenoviridae,Circoviridae,Orthoherpesviridae,Papillomaviridae,ParvoviridaeandPolyomaviridaeand assessed their phylogenetic relationships to known viruses. Endemic lemurs and tufted-tailed rats displayed particularly novel DNA viral diversity mirroring the geographic isolation and subsequently rich evolutionary history of their hosts. Notably, we provide the first coding-complete sequences in lemurs of herpesviruses, polyomaviruses, adeno-associated viruses and circoviruses. In contrast, the DNA viral communities of black rats in Madagascar were similar to those found in globally distributed black and brown rat populations, given their broad geographic spread and relatively recent introduction to the island. Given the scarcity of viral research in natural populations of lemurs and rodents in Madagascar despite the island’s exceptional biodiversity and escalating anthropogenic pressures, this study provides a genomic and phylogenetic foundation for DNA viruses infecting Malagasy lemurs and rodents.
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- Award ID(s):
- 2314898
- PAR ID:
- 10703647
- Publisher / Repository:
- Microbial Genomics
- Date Published:
- Journal Name:
- Microbial Genomics
- Volume:
- 12
- Issue:
- 5
- ISSN:
- 2057-5858
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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