Data from: Climate change and human colonization triggered habitat loss and fragmentation in Madagascar.

The relative effect of past climate fluctuations and anthropogenic activities on current biome distribution is subject to increasing attention, notably in biodiversity hotspots. In Madagascar, where humans arrived in the last ~4-5,000 years, the exact causes of the demise of large vertebrates that cohabited with humans is yet unresolved. The prevailing narrative holds that Madagascar was covered with forest before human arrival, and that the expansion of grasslands was the result of human driven deforestation. However, recent studies have shown that vegetation and fauna structure substantially fluctuated during the Holocene. Here we study the Holocene history of habitat fragmentation in the north of Madagascar using a population genetics approach. To do so we infer the demographic history of two northern Madagascar neighboring, congeneric, and critically endangered forest dwelling lemur species - Propithecus tattersalli and P. perrieri - using population genetic analyses. Our results highlight the necessity to consider population structure and changes in connectivity in demographic history inferences. We show that both species underwent demographic fluctuations which most likely occured after the mid-Holocene transition. While mid-Holocene climate change probably triggered major demographic changes in the two lemur species range and connectivity, human settlements that expanded over the last four millennia in northern Madagascar likely played a role in the loss and fragmentation of the forest cover.

过往气候波动与人类活动对当前生物群系（biome）分布的相对影响正受到学界越来越多的关注，在生物多样性热点地区尤为显著。在人类于距今约4000至5000年前抵达的马达加斯加，与人类共生的大型脊椎动物灭绝的确切原因至今仍未明晰。主流观点认为，人类抵达前的马达加斯加全境被森林覆盖，而草原的扩张则是人类驱动的森林砍伐所导致的结果。然而，近期研究表明，全新世（Holocene）期间的植被与动物群落结构曾发生显著波动。本研究借助群体遗传学（population genetics）方法，探究马达加斯加北部全新世时期的栖息地破碎化历史。为此，我们通过群体遗传分析，对马达加斯加北部两种同属、栖息于森林且极度濒危的狐猴（lemur）物种——Propithecus tattersalli与P. perrieri——的种群历史进行推断。本研究结果强调，在种群历史推断过程中必须考虑种群结构与连通性变化。研究显示，这两种狐猴均经历了种群数量波动，且该波动极有可能发生在全新世中期过渡之后。尽管全新世中期的气候变化可能引发了这两种狐猴分布范围与连通性的重大变化，但过去四千年来在马达加斯加北部不断扩张的人类定居活动，或许也对森林覆盖面积的缩减与破碎化起到了推动作用。