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Abstract The aye-aye (Daubentonia madagascariensis) is the only extant member of the Daubentoniidae primate family. Although several reference genomes exist for this endangered strepsirrhine primate, the predominant usage of short-read sequencing has resulted in limited assembly contiguity and completeness, and no protein-coding gene annotations have yet been released. Here, we present a novel, fully annotated, chromosome-level hybrid de novo assembly for the species based on a combination of Oxford Nanopore Technologies long reads and Illumina short reads and scaffolded using genome-wide chromatin interaction data—a community resource that will improve future conservation efforts as well as primate comparative analyses.
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Fossil lemurs from Egypt and Kenya suggest an African origin for Madagascar’s aye-aye
Abstract In 1967 G.G. Simpson described three partial mandibles from early Miocene deposits in Kenya that he interpreted as belonging to a new strepsirrhine primate,Propotto. This interpretation was quickly challenged, with the assertion thatPropottowas not a primate, but rather a pteropodid fruit bat. The latter interpretation has not been questioned for almost half a century. Here we re-evaluate the affinities ofPropotto, drawing upon diverse lines of evidence to establish that this strange mammal is a strepsirrhine primate as originally suggested by Simpson. Moreover, our phylogenetic analyses support the recognition ofPropotto, together with late EocenePlesiopithecusfrom Egypt, as African stem chiromyiform lemurs that are exclusively related to the extant aye-aye (Daubentonia) from Madagascar. Our results challenge the long-held view that all lemurs are descended from a single ancient colonization of Madagascar, and present an intriguing alternative scenario in which two lemur lineages dispersed from Africa to Madagascar independently, possibly during the later Cenozoic.
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- Award ID(s):
- 1638796
- PAR ID:
- 10153575
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 9
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Hurst, Laurence D (Ed.)Every mammal studied to date has been found to have a male mutation bias: male parents transmit more de novo mutations to offspring than female parents, contributing increasingly more mutations with age. Although male-biased mutation has been studied for more than 75 years, its causes are still debated. One obstacle to understanding this pattern is its near universality—without variation in mutation bias, it is difficult to find an underlying cause. Here, we present new data on multiple pedigrees from two primate species: aye-ayes (Daubentonia madagascariensis), a member of the strepsirrhine primates, and olive baboons (Papio anubis). In stark contrast to the pattern found across mammals, we find a much larger effect of maternal age than paternal age on mutation rates in the aye-aye. In addition, older aye-aye mothers transmit substantially more mutations than older fathers. We carry out both computational and experimental validation of our results, contrasting them with results from baboons and other primates using the same methodologies. Further, we analyze a set of DNA repair and replication genes to identify candidate mutations that may be responsible for the change in mutation bias observed in aye-ayes. Our results demonstrate that mutation bias is not an immutable trait, but rather one that can evolve between closely related species. Further work on aye-ayes (and possibly other lemuriform primates) should help to explain the molecular basis for sex-biased mutation.more » « less
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