Can elephants cry?

Earlier this week a conservation group published an image of an elephant they had rescued. The animal appeared to be crying - some said with relief and joy - prompting the pictures to go viral.

The BBC's Victoria Gill wanted to investigate whether elephants can really cry and she discussed what she'd uncovered with Chris Smith...

Victoria - This is a story that seems to have captured the public imagination all around the world actually this week. A conservation organisation called Wildlife SOS reported that they had rescued an elephant called Raju who had been treated appallingly for apparently 50 years. He'd actually been sort of passed from pillar to post being kept as a begging elephant. He was chained in these horrendous shackles that had spikes on them around his legs that produce very nasty wounds. This was in India. He was in very terrible condition. He was very, very thin and this conservation organisation, the good news story is that they rescued him. But the story that really captured the imagination was this picture of Raju after he was rescued that appeared to show this big streak that looked like a tear running down his face. And so, this conservation organisation and lots of news outlets reported that this elephant had wept with joy. I'm not sure there's any evidence to support that.

Chris - So, you're saying that it is exclusively humans that cry.

Victoria - It seems to be, yeah. I think what we've got here is a case of convenience and probably quite campaigning anthropomorphism. Elephants actually, like a lot of mammals, apart from the mammals that live in water have these lacrimal glands that produce this sort of aqueous - the liquid part of our tears. Our eyes, in order to move around in our sockets and be bathed and protected and protected from bacteria as well have to be constantly bathed in this fluid. And so, lots and lots of these land dwelling mammals produce tears. And actually, elephants are really interesting because they have lots of glands around their eyes that produce different liquids, not just the kind of salty, aqueous tears that we produce. Young males when they're in what's called 'must' which is a kind of high testosterone, very sexually active period, this hormonal response will actually make them produce even more of these secretions. If you go to a safari park, if you go to a zoo, you will see what look like tears streaming down their face, but there's no evidence at all that these are emotional tears, that they're crying like us. That seems to be an exclusively human physiological thing.

Chris - I think there's also some evidence that according to what mood a person is in - human - the composition of their tears changes too. So, there's a difference between emotional tears, sadness, happy tears, and eye-watering because you've got something in your eye type tears.

Victoria - Yeah, there is. I mean, still actually a lot of mystery, kind of evolutionary mystery surrounding why we actually produce tears. I mean, it's something that puzzled even Darwin. There's a really nice book called "Why humans weep." It's a really interesting book and it sort of talks about how our crying actually changes as we mature. Babies and small children are very, very vocal in their crying. As we go to maturity, we will cry very quietly and just produce these tears. What he suggests is that that kind of silent weeping is actually a protective mechanism because if we can show to our social group, our family group around us that we're distressed and we need help, but not call out and make an involuntary sound, that means that the predators won't be able to hear that we're in distress but will be able to give a signal to our group that we need some help.

Chris - Indeed because some people suggest that because so much of our brain - I think a third of, our brain is given over to decoding what we're looking at, we've naturally evolved to have very visual signs of how we're feeling whereas other animals including elephants, they tend to have much better developed senses of other types. And so for them, a physical visible signal like a tear running down their face would be quite literally lost in such a huge area of a face that probably would be less useful to them as a signal.

Victoria - Exactly and with animals whose sense of smell, whose other senses as you say are so much more important to them. Interestingly, we don't seem to be the only animals that will cry as in cry out because if you define crying as an emotional response to distress that might be a vocal response, we've seen that in elephants. We've seen what seems to be collective grieving even. So, there've been observations of elephants gathering around the bodies of deceased elephants in groups. There've been different responses from the different animals in that group and some appear to rock their bodies in response which sounds, anthropomorphising again, like a very human-like distress-like response, that sort of rocking. So, we may well not be the only animals that cry. In fact, we don't seem to be, but we're the only animal that produces these emotional tears, and there's still so much evolutionary mystery around that.

Chris - So, how has it gone down then, your analysis of the fact that the elephant probably wasn't really crying? Has it been well-received or have people shed a tear or two over the fact that elephants don't seem to cry?

Victoria - I think I managed to dampen the nation's spirits by sort of bringing in a little bit of what I thought was quite interesting, sort of actual animal behaviour observation - a bit of ethology, a bit of science into it to just say, "Well, no.  there's no evidence of this" but the physiology of elephants and actually, all the glands around their eyes is really interesting. So certainly, this elephant was producing tears but they weren't emotional tears. I think there was a little bit of not letting science get in the way of a good story there I'm afraid.