Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, , 0316 Oslo, Norway, School of Biology and Environment Science, University of College Dublin, , Belfield, Dublin 4, Republic of Ireland, UCD Earth Institute, University of College Dublin, , Belfield, Dublin 4, Republic of Ireland.
Proc Biol Sci. 2014 Jan 22;281(1778):20132312. doi: 10.1098/rspb.2013.2312. Print 2014 Mar 7.
The ecological and evolutionary processes leading to present-day biological diversity can be inferred by reconstructing the phylogeny of living organisms, and then modelling potential processes that could have produced this genealogy. A more direct approach is to estimate past processes from the fossil record. The Carnivora (Mammalia) has both substantial extant species richness and a rich fossil record. We compiled species-level data for over 10 000 fossil occurrences of nearly 1400 carnivoran species. Using this compilation, we estimated extinction, speciation and net diversification for carnivorans through the Neogene (22-2 Ma), while simultaneously modelling sampling probability. Our analyses show that caniforms (dogs, bears and relatives) have higher speciation and extinction rates than feliforms (cats, hyenas and relatives), but lower rates of net diversification. We also find that despite continual species turnover, net carnivoran diversification through the Neogene is surprisingly stable, suggesting a saturated adaptive zone, despite restructuring of the physical environment. This result is strikingly different from analyses of carnivoran diversification estimated from extant species alone. Two intervals show elevated diversification rates (13-12 Ma and 4-3 Ma), although the precise causal factors behind the two peaks in carnivoran diversification remain open questions.
通过重建现存生物的系统发育，然后模拟可能产生这种系统发育的潜在过程，可以推断出导致当今生物多样性的生态和进化过程。一种更直接的方法是根据化石记录来估计过去的过程。食肉目（哺乳动物）既有丰富的现存物种多样性，也有丰富的化石记录。我们为近 1400 种食肉动物的 10000 多个化石出现地点编制了物种水平的数据。利用这一汇编，我们通过中新世（2200-200 万年前）估计了食肉动物的灭绝、物种形成和净多样化，同时对采样概率进行了建模。我们的分析表明，犬形目（狗、熊和它们的亲属）的物种形成和灭绝率高于猫形目（猫、鬣狗和它们的亲属），但净多样化率较低。我们还发现，尽管物种不断更替，但通过中新世的食肉动物净多样化仍然惊人地稳定，这表明尽管物理环境发生了重组，但适应区已经饱和。这一结果与仅从现存物种推断的食肉动物多样化分析截然不同。有两个时期的多样化率较高（1300-1200 万年前和 400-300 万年前），尽管导致食肉动物多样化的两个高峰的确切因果因素仍悬而未决。
