Image from J. W. Buel, Heroes of the Dark Continent (1889), p140

By Oscar Wilson, Michael Pashkevich, Kees Rookmaaker, and Edgar Turner.

This Plain Language Summary is published ahead of the article discussed; check back soon for a link to the full paper.

Rhinos are among the most charismatic and well-known mammals on Earth, but face extinction because of human activities: hunting and habitat conversion. To learn how to save rhinos, we need as much information as possible about how their relationship with humans has changed over time.

The Rhino Resource Center (RRC), which can be found at, is the largest online collection of information about rhinos, including thousands of pictures and pieces of literature about all five rhino species. We used the artwork and photos available on the website to answer two questions related to rhino conservation: 1) How have the relationships between humans and rhinos changed over time? 2) Has rhino horn length changed over time? By answering these questions, we assessed the value of online databases, like the RRC, for understanding long-term changes in human interactions with nature, and changes in the physical characteristics of species.

By analysing themes in images over time, we found that the relationship between humans and rhinos has been changing from the 16th century onwards. After people created the first images, rhinos were mostly an exciting curiosity for artists in Europe, until empires expanded and hunting became more common. Since the middle of the 20th century, the importance of conservation and nature has increased. Using photographs, we also found evidence for a decrease in rhino horn length since the 19th century, possibly related to hunting pressure. Our study indicates that images are a powerful tool in understanding the relationships between humans and large mammals, and researchers can also use images in studies of evolution. We propose that developing and mining similar databases could be a valuable way to learn more about other large animals like elephants, tapirs or antelopes.