Data from: Novel opsin gene variation in large-bodied, diurnal lemurs

Some primate populations include both trichromatic and dichromatic (red–green colour blind) individuals due to allelic variation at the X-linked opsin locus. This polymorphic trichromacy is well described in day-active New World monkeys. Less is known about colour vision in Malagasy lemurs, but, unlike New World monkeys, only some day-active lemurs are polymorphic, while others are dichromatic. The evolutionary pressures underlying these differences in lemurs are unknown, but aspects of species ecology, including variation in activity pattern, are hypothesized to play a role. Limited data on X-linked opsin variation in lemurs make such hypotheses difficult to evaluate. We provide the first detailed examination of X-linked opsin variation across a lemur clade (Indriidae). We sequenced the X-linked opsin in the most strictly diurnal and largest extant lemur, Indri indri, and nine species of smaller, generally diurnal indriids (Propithecus). Although nocturnal Avahi (sister taxon to Propithecus) lacks a polymorphism, at least eight species of diurnal indriids have two or more X-linked opsin alleles. Four rainforest-living taxa—I. indri and the three largest Propithecus species—have alleles not previously documented in lemurs. Moreover, we identified at least three opsin alleles in Indri with peak spectral sensitivities similar to some New World monkeys.部分灵长类种群因X连锁视蛋白基因座（X-linked opsin locus）存在等位基因变异，同时拥有三色视觉与二色视觉（红绿色盲）个体。这种多态性三色视觉在昼行性新世界猴中已有充分研究。目前对马达加斯加狐猴的色觉了解较少，但与新世界猴不同，仅部分昼行性狐猴存在该多态性，其余则为二色视觉。狐猴间此类差异背后的进化选择压力尚不清楚，但有假说认为物种生态学特征（包括活动模式差异）可能发挥作用。由于狐猴X连锁视蛋白变异的相关数据有限，此类假说难以得到验证。本研究首次对狐猴类群——大狐猴科（Indriidae）的X连锁视蛋白变异进行了系统性详细分析。我们对现存体型最大、严格昼行的狐猴物种——大狐猴（Indri indri），以及9种隶属于冕狐猴属（Propithecus）的体型通常较小的昼行性大狐猴科物种的X连锁视蛋白进行了测序。尽管与冕狐猴属（Propithecus）为姊妹群的夜行性毛狐猴属（Avahi）不存在该多态性，但至少有8种昼行性大狐猴科物种拥有2种及以上的X连锁视蛋白等位基因。4种栖息于雨林的类群——大狐猴（I. indri）与3种体型最大的冕狐猴属物种，拥有此前在狐猴中未被记录的等位基因。此外，我们在大狐猴中鉴定出至少3种视蛋白等位基因，其光谱敏感峰值与部分新世界猴相近。