In the 1570s, when King Philip II of Spain sent emissaries to survey the flora and fauna of villages in central and southern Spain, he wasn’t thinking about ecological networks or extinction. He just wanted to know exactly what he owned. So, he asked at least two people in each village to describe the land, flora, and fauna of their territory to his surveyors. Now, 450 years later, a team of ecologists says the resulting answers to that survey have value as ecological surveys, taken before the word “ecology” entered the lexicon.
“I think it’s brilliant,” said Ana Rodrigues, a conservation biologist at the Center of Functional and Evolutionary Ecology in France who was not part of the research. “The survey was a historical document and now it becomes ecological data.”
The new work was done by Duarte Viana, an ecologist at the Doñana Biological Station (part of Spain’s National Research Council), and his colleagues. They used the answers to the king’s questionnaires and transcriptions from historians to create a list of plants, animals, and their respective ecological niches, providing an environmental snapshot of Castile, a large kingdom that was in modern-day central and southern Spain, from nearly 500 years ago. In their work, published recently in Ecology, they found various animals that lived and roamed across central Spain are now restricted to the north of Spain, whereas some plants that are abundant in the country now weren’t around in the 16th century.
Other similar inventories based on historical documents do exist, Viana says. For instance, researchers in 2018 gathered ecological information from 400 years ago using a 17th century natural history text from Scotland, but that text was also a science text, Viana explains, making his team’s work—using a document that was not an obvious work of science—unique.
Viana’s team chose to analyze questionnaires from 1574, 1575, and 1578. King Philip II had villagers in the kingdom answer questions about plants and animals, how people made a living, available natural resources such as wood, and social organization, including the number of households in a given village.
The locals, who may not have been literate, likely told their responses to the surveyors, who wrote them down in old Castilian. Then, early 20th century historians translated these responses into modern Spanish. Viana and his team mostly used these transcriptions to make sense of the old documents.
The researchers focused their inventory on flora and fauna deemed important to be able to re-create 16th century habitats, such ase the Cantabrian brown bear, Iberian wolf, and the holm oak tree (Quercus ilex or Quercus rotundifolia), which are all considered national species in Spain. The team’s focus also included natural resources important in 16th century Spain, such as animals the villagers could hunt or fish and ones that had medicinal uses, such as leeches. They also considered dangerous species such as wolves and bears. In all, the team collected 7309 records of 75 wild plants, 89 wild animals, and 60 domesticated plants and animals.
They found that in the 16th century, the Cantabrian brown bear and Iberian wolf both used to live in central Spain, which has a different climate and habitat than their present-day habitat of northern Spain. The European eel (Anguilla anguilla) was distributed across all of Spain’s principal bodies of water, but construction projects in these bodies of water meant eels today have been trapped and confined to only Spain’s estuaries.
But other findings served to reinforce present-day knowledge. For example, some species thought to be native to Spain, such as freshwater crayfish, didn’t seem to be present in the 16th century, which is consistent with the fact that some species were only introduced in Spain much later.
Knowing the ecological history of different species could shape how conservationists approach their efforts, Viana said. The European eel, for example, is categorized as critically endangered by the International Union for Conservation of Nature’s Red List of Threatened Species, whereas the Cantabrian brown bear is classified as vulnerable, so scientists may be able to use its historical whereabouts to increase protections.
Some animals never made it to modern day. Only two villages, for instance, reported seeing the zebro, an ancient wild “donkey horse” that had stripes similar to today’s zebras but gray hair reminiscent of donkeys and horses. When the team compared the mentions of zebros—which is also where modern day zebras get their name—in the 16th century questionnaires with mentions in historical documents from the 18th century, they realized the animal wasn’t mentioned in the later documents likely because it was going through its extinction at the time. “It was a live story of the extinction of that species,” Viana said.
María Portuondo, a retired historian of science at John Hopkins University who was not involved in the study, cautions that it’s hard to verify the authenticity of the responses in the questionnaires given the many steps to translation. Not only were the original responses translated before being written down, a Spanish overlord—a mayor, governor, or parish priest—likely also edited them, she said. And 20th century historians likely edited the responses yet again, as they translated and published more digestible versions of the answers of the questionnaire. “The Spanish translators, in their effort to make it intelligible in Spanish, might have translated the name as a wolf when it meant a panther,” Portuondo explained.
Viana acknowledges that even with the translations, it was “really difficult” in some cases to understand what the villagers were referring to, especially when they used region-specific names. To counter this, the researchers went through lists of synonyms and vernacular names of species to identify the plant or animal being referenced.
Portuondo says other historians who might hope to use the ecology inventory might run into similar issues. “So, let’s say you’ve never seen a mongoose, and somebody described it to you as a ‘ferret, but a little bigger.’ You’d get the picture,” Portuondo explained. “The challenge is that for modern-day biologists, it does matter whether the actual animal around 450 years ago was a ferret or a mongoose. That’s the challenge of using 450-year-old questionnaires!”
For Rodrigues, who specializes in conservation of biodiversity at large scales, this new study’s compilation of species offers a starting point from which she can study ecosystems over time. She added that this study can provide an idea of how nature actually was and not how we might have assumed it was in the 16th century.
This is the hope of the investigators behind the data set, that the inventory can help give scientists a broader picture of where species existed. By doing this study, Viana and his team were able to paint a picture of individual species in the past, but they hope, with time, to also get a sense of how different species coexisted. And perhaps, with better conservation efforts, some of those past relationships could be resurrected. “We can only imagine how the interaction between the major [animals] in the Iberian Peninsula could have been in the past. Will we witness it again?” Viana said.
Source: Science Mag