Data from: An updated global dataset for diet preferences in terrestrial mammals: testing the validity of extrapolation

1. Diet is a key trait of an organism’s life history that influences a broad spectrum of ecological and evolutionary processes. Kissling et al. (2014) compiled a species-specific dataset of diet preferences of mammals for 38% of a total of 5364 terrestrial mammalian species assessed for the International Union for Conservation of Nature’s Red List, to facilitate future studies. The authors imputed dietary data for the remaining 62% by using extrapolation from phylogenetic relatives. 2. We collected dietary information for 1261 mammalian species for which data were extrapolated by Kissling et al. (2014), in order to evaluate the success with which such extrapolation can predict true diets. 3. The extrapolation method devised by Kissling et al. (2014) performed well for broad dietary categories (consumers of plants and animals). However, the method performed inconsistently, and sometimes poorly, for finer dietary categories, varying in accuracy in both dietary categories and mammalian orders. 4. The results of the extrapolation performance serve as a cautionary tale. Given the large variation in extrapolation performance, we recommend a more conservative approach for inferring mammalian diets, whereby dietary extrapolation is implemented only when there is a high degree of phylogenetic conservatism for dietary traits. Phylogenetic comparative methods can be used to detect and measure phylogenetic signal in diet. If data for species are needed, then only the broadest feeding categories should be used. This would ensure a greater level of accuracy and provide a more robust dataset for further ecological and evolutionary analysis.1. 饮食是生物体生活史的关键性状，可影响广泛的生态与进化过程。Kissling等人（2014）为推动后续研究，针对国际自然保护联盟（International Union for Conservation of Nature, IUCN）红色名录评估的5364种陆生哺乳动物中38%的物种，汇编了物种特异性的饮食偏好数据集。对于剩余62%的物种，作者通过系统发育近缘类群的外推法补全了其饮食数据。 2. 本研究收集了Kissling等人（2014）通过外推法获得饮食数据的1261种哺乳动物的实测饮食信息，以评估此类外推法预测真实饮食的准确性。 3. Kissling等人（2014）提出的外推法在宽泛饮食类别（如植物与动物食性类群）中表现良好，但针对精细饮食类别时，该方法的表现并不一致，且有时效果欠佳，其准确性在不同饮食类别和哺乳动物目级类群中均存在较大差异。 4. 该外推法的性能评估结果可作为一项警示案例。鉴于外推性能存在较大波动，我们建议采用更为保守的方案推断哺乳动物饮食：仅当饮食性状存在高度系统发育保守性时，方可实施饮食外推。可借助系统发育比较方法检测并量化饮食性状的系统发育信号。若需获取物种饮食数据，则仅应使用最宽泛的摄食类别，此举可保障更高的准确性，并为后续生态与进化分析提供更为稳健的数据集。