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1. Online image repositories can offer a freely accessible, information-rich and cost-effective alternative to museum collections for studying long-term changes in human interactions with nature and ecological and evolutionary change. The Rhino Resource Center (RRC) is one example, curated by experts and holding a collection of >4000 rhino images, including both artistic portrayals (1481-2021) and photographs (taken between 1862-2021), and representing a potentially valuable case study to investigate the utility of online image repositories for research into large vertebrates and, potentially, other well-recorded smaller taxa. The five extant species of rhino are all threatened by habitat loss and human hunting and therefore are an important focus for conservation research.2. We used the RRC for two separate research approaches: (i) assessing the changing representations and human interactions with rhinos using 3158 images (1531 pieces of artwork and 1627 photographs); and (ii) determining to what extent morphological data can be extracted from photographs to assess changes in horn length over time, using a sample size of 80 photographs of rhinos taken in profile view.3. We found that African rhino species have become more commonly depicted in images, compared to Asian rhino species over time. During the age of European imperialism (between the 16th and 20th centuries), rhinos were commonly portrayed as hunting trophies, but since the mid-20th century, they have been increasingly portrayed in a conservation context, reflecting a change in emphasis from a more to less consumptive relationship between humans and rhinos. Finally, we found evidence for declining horn length over time across species, perhaps related to selective pressure of hunting, and indicating a utility for image-based approaches in understanding societal perceptions of large vertebrates and trait evolution.

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<p>The Early Pleistocene dispersal of <em>Homo </em>out of Africa  is a highly studied and debated topic.  One of the controversies centres on the question of what type of environments hominin species expanded out of Africa into. We conducted a literature review of 163 papers published since 2000 studying the environmental settings of the first Out of Africa expansion. We found that the literature is polarised between two types of hypotheses. On one hand there are papers which describe <em>Homo</em> in the Early Pleistocene as inflexible (compared to <em>Homo sapiens</em>) and incapable of persisting in non-savannah environments, e.g. the ‘savannahstan’ hypothesis. On the other hand there are papers which describe <em>Homo</em> as flexible and able to persist in various environment types, e.g. the variability selection hypothesis. By investigating these hypotheses we are able to move closer to answering the question - as <em>Homo </em>dispersed out of Africa, did they diversify to exploit new environments, or remain within the ranges of their African niche? We analysed the reconstructions of early <em>Homo</em> environments included in these papers. We found that the qualitative language used to describe hominin environments is problematic and impedes the formation of clear conclusions about the environments occupied by early <em>Homo</em> species. However, by forcibly quantifying the descriptions used in 69 (of the original 163) papers we found that the research does not strongly support the savannahstan hypothesis. Instead the environments inhabited by <em>Homo</em> are consistently reconstructed as a mix of environment types (grassland, forest, savannah etc.), with a slight skew towards open habitats. Based on these results, we tentatively suggest that <em>Homo </em>exhibited a preference for heterogeneous “edge” environments during the Pleistocene and as they dispersed out of Africa. However,  in order to further investigate the potential preference of<em> Homo </em>for heterogeneous environments and to build confidence in reconstructions of early human environments in general, quantified reconstructions of the vegetation composition and distribution at early <em>Homo</em> sites are needed. </p>