For more than a hundred years, scientists believed that only one species of rabbit lived in the Iberian Peninsula, with at most two regional species. A new study has completely overturned this idea.
Researchers from Spain, Portugal and the UK have discovered that what looks like a single rabbit is actually two separate species that separated nearly two million years ago. One of these species, now called the Iberian rabbit, is quietly disappearing in parts of Portugal and southwestern Spain, while the other, the common European rabbit, continues to thrive and even spread into many areas. This discovery could change how conservationists protect these animals in the future.
How researchers uncovered two separate… Types of rabbits
The findings come from a study titled When Taxonomy Lags Evolution, which was published in the journal Conservation Biological. It was led by Rafael Villafuerte and Miguel Delibes Mateus from the Institute of Advanced Social Studies in Spain, working alongside researchers from the TRAMAS group and its institutions in Portugal and the UK, including BIOPOLIS and CIBIO at the University of Porto. By combining genetic data with physical measurements, the team found that the two rabbit lineages evolved separately approximately two million years ago and no longer interbreed naturally, meeting the standard scientific definition of separate species rather than simply regional variants of the same animal.
The difference between the Iberian rabbit and the European rabbit
The two species now recognized are the Iberian rabbit, known scientifically as Oryctolagus algirus, and the European rabbit, known as Oryctolagus cuniculus. The Iberian rabbit is found naturally throughout Portugal and western Spain, and is found nowhere else in the world except a few Atlantic islands and parts of North Africa, where it was introduced by humans long ago. The European rabbit, on the other hand, originated in eastern Spain, but has since been introduced by humans across large parts of Europe, Oceania and South America, making it one of the most widespread mammals on the planet.
Physically, the two species are not identical either, with the Iberian rabbit being generally smaller and bearing darker fur than its European relative.
Why is one type of rabbit declining while another is spreading?
What worries researchers most is what this hidden diversity has hidden for so long. While European rabbits remain stable or even increasing across much of their range, to the point of damaging crops in some areas, Iberian rabbits are experiencing a sharp decline in the areas they call home.
Because both were treated as the same species for so long, conservation efforts failed to notice just how badly one of them was suffering.
Miguel Delibes Mateus explained that the two rabbits cannot continue to be managed as if they were one animal, as they have followed separate evolutionary paths for nearly two million years.
How does mismanagement exacerbate decline?
The problem is not just about labeling. According to the researchers, wildlife restocking programs aimed at increasing rabbit populations for hunting or ecological purposes often release European rabbits into areas where only the Iberian rabbit naturally lives, because European rabbits are more abundant and reproduce faster.
This practice risks accelerating the disappearance of the Iberian rabbit through competition for food and habitat, while also complicating the maintenance of the distinct genetic lineage of the Iberian rabbit, further blurring the already thin genetic boundaries between them.
If left unchecked, this could wipe out a species that has been around for nearly two million years before most people realize it’s gone, researchers warn.
What does official recognition of conservation mean?
The researchers who conducted this study are now calling for the Iberian rabbit to be officially reclassified as its own distinct species rather than a subspecies. According to BIOPOLIS and CIBIO, this change will not involve the discovery of a new or unfamiliar animal, but rather correctly identify and name a breed that has already been genetically identified, and give it the necessary legal and scientific status to prevent its extinction through replacement.
If wildlife agencies officially treat the Iberian rabbit as a separate species, they will need their own population assessments, their own conservation goals, and stricter controls on restocking practices that currently blur the line between the two groups.
Why this discovery is important beyond rabbits
Rabbits play a large role in Iberian ecosystems, forming a major food source for endangered predators such as the Iberian lynx and Spanish imperial eagle, both of which rely heavily on healthy rabbit populations for survival. So the decline in Iberian rabbit numbers could ripple outward, affecting the very predators that conservationists have spent decades trying to protect. This study is a reminder that biodiversity can hide in plain sight, and that even a familiar and familiar animal can hold secrets that take genetics and nearly two million years of separation to finally be revealed.