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Species distribution models (SDMs) are widely used to project how species distributions may vary over time, particularly in response climate change. Although the fit of such models to current distributions is regularly enumerated, SDMs are rarely tested across longer time spans to gauge their actual performance under environmental change. Here, we utilise paleozoological presence/absence records to independently assess the predictive accuracy of SDMs through time. To illustrate the approach, we focused on modelling the Holocene distribution of the hartebeest, Alcelaphus buselaphus , a widespread savannah-adapted African antelope. We applied various modelling algorithms to three occurrence datasets, including a point dataset from online repositories and two range maps representing current and 'natural' (i.e. hypothetical assuming no human impact) distributions. We compared conventional model evaluation metrics which assess fit to current distributions (i.e. True Skill Statistic, TSS c , and Area Under the Curve, AUC c ) to analogous 'paleometrics' for past distributions (i.e. TSS p , AUC p , and in addition Boyce p , F2-score p and Sorensen p ). Our findings reveal only a weak correlation between the ranking of conventional metrics and paleometrics, suggesting that the models most effectively capturing present-day distributions may not be the most reliable to hindcast historical distributions, and that the choice of input data and modelling algorithm both significantly influences environmental suitability predictions and SDM performance. We thus advocate assessment of model performance using paleometrics, particularly those capturing the correct prediction of presences, such as F2-score p or Sorensen p , due to the potential unreliability of absence data in paleozoological records. By integrating archaeological and paleontological records into the assessment of alternative models' ability to project shifts in species distributions over time, we are likely to enhance our understanding of environmental constraints on species distributions., Competing Interests: No conflict of interest is reported., (© 2024 The Author(s). Ecology and Evolution published by John Wiley & Sons Ltd.)

Finding suitable forage patches in a heterogeneous landscape, where patches change dynamically both spatially and temporally could be challenging to large herbivores, especially if they have no a priori knowledge of the location of the patches. We tested whether three large grazing herbivores with a variety of different traits improve their efficiency when foraging at a heterogeneous habitat patch scale by using visual cues to gain a priori knowledge about potential higher value foraging patches. For each species (zebra ( Equus burchelli ), red hartebeest ( Alcelaphus buselaphus subspecies camaa ) and eland ( Tragelaphus oryx )), we used step lengths and directionality of movement to infer whether they were using visual cues to find suitable forage patches at a habitat patch scale. Step lengths were significantly longer for all species when moving to non-visible patches than to visible patches, but all movements showed little directionality. Of the three species, zebra movements were the most directional. Red hartebeest had the shortest step lengths and zebra the longest. We conclude that these large grazing herbivores may not exclusively use visual cues when foraging at a habitat patch scale, but would rather adapt their movement behaviour, mainly step length, to the heterogeneity of the specific landscape., Competing Interests: The authors declare there are no competing interests.

The composition of major nutrients and fatty acids of the milk of three species, red hartebeest, Southern reedbuck and warthog, and milk fatty acids of giraffe, that have not been published before, are reported, and together with the same parameters of 11 species previously published, were incorporated in a phylogenetic comparison. Unique properties of milk composition have been observed. Southern reedbuck milk seems to have a complex casein composition, similar to that of sheep. Milk composition varies between species. Although some differences may be ascribed to biological condition, such as stage of lactation, or ecological factors, such as availability of certain nutrients, the contribution by evolutionary history is not well documented and the emphasis is usually on the composition of the macro nutrients. Phylogenetic comparisons often lack representatives of multiple species of taxonomic groups and sub-groups. To date phylogenetic comparisons of milk composition have been carried out by using data from different publications. The problem with this approach is that the ecological factors cannot be completely ruled out. A statistical phylogenetic comparison by PCA between 15 species representing 7 different suborders, families or subfamilies of African Artiodactyla was carried out. The phylogenetic properties showed that the milk composition of the Bovinae, represented here by the subfamilies Bovini and Tragelaphini, differs from the other taxonomic groups, in that the Alcelaphinae had a high milk fat content of the medium chain length fatty acids C8-C12 (>17% of total fatty acids) and the Hippotraginae high amounts of oligosaccharides (>0.4%)., (Copyright © 2016 Elsevier Inc. All rights reserved.)