How science is slowly tearing down Aristotle’s ladder of nature

As scientists design new ways of testing the mental aptitude of animals, they’re finding that many species are smarter than previously thought. The Wall Street Journal recently examined the trend, pointing out that tests sometimes need just slight alterations before they’re ideally suited for a given animal. One example is self awareness in elephants: some prior studies indicated the creatures couldn’t recognize their own reflection in a mirror, but newer attempts suggest Increasing the size of that reflective surface leads to more promising results. Other studies provide at least some evidence that animals care about the well-being of their own species. Apes and rats have both shown signs of empathy when tested under proper circumstances. In short, Aristotle’s ladder of nature is continually being upended as we ourselves learn how to best pick an animal’s brain.