Perhaps measuring animal intelligence by comparing it to human intelligence isn't the best litmus test. As Mark Twain once said, "It is just like man's vanity and impertinence to call an animal dumb because it is dumb to his dull perceptions."
But, in the just-released Cambridge Declaration on Consciousness, witnessed by Stephen Hawking, a prominent group of scientists has declared that humans are not unique in ways that matter. Says the panel, "Non-human animals, including all mammals and birds, and many other creatures, including octopuses, also possess these [same] neurological substrates [as human beings]." Yes, they stand on their toes or tentacles, snatch their offspring from their arms or their arboreal nests, and they feel the same way about it as would you or I. The question is, how is this knowledge to inform our behavior? After all, shouldn't it?
Of course, hundreds of studies have already demonstrated animals' logical, mathematical, linguistic, and emotional intelligence. For example, for years we blithely believed that humans were the only species to use tools, until researchers documented that wasps were using pebbles as hammers, octopuses were carrying coconut shells as portable hiding places, crows were using sticks to dig in the ground for grubs and many other examples. The mathematical abilities of fish have proved to be on a par with those of monkeys, dolphins and bright young human children.
We know that elephants flirt with each other and gather to grieve over the loss of a loved one, that cows shed tears, and that monkeys have refused to pull a chain to access their only source of food if doing so caused another monkey, even a stranger, to experience a painful electric shock. In that famous study, one monkey starved and went without water for nearly two weeks to avoid hurting his fellow. When the experiment was repeated, other monkeys also chose to starve rather than giving shocks to another monkey. A similar study done with human subjects showed that 65 percent of people continued to give other people increasingly strong electric shocks if an experimenter simply told them to do so. It's not the monkeys who need their heads examined!
While miscommunication is blamed for many human calamities, chicks are able to cluck back and forth with their mothers from inside their shells before they are even hatched. Chickens!
One of the Declaration's signatories is Irene Pepperberg, whose work with a parrot named Alex showed that birds can learn meaningful English, count and identify colors, objects and shapes. Alex could even communicate his feelings in English.
Can any human speak even one word of another animal's language? No, but perhaps it's better that way, because if we could speak to them, how would we explain our systematic use and abuse of all the other species?
Can humans smell nuances of fragrance on the individual petals of a single rose and know whether insects have landed on it or human hands have touched it? No, but dogs can, and they try their best to, despite being dragged along by an impatient human anxious to get to Starbucks before work. Can humans navigate using only the sky's polarized light? No, but bees can. Can humans change the color of their skin to blend in with their surroundings or keep an aggressive rival at bay? No, but cuttlefish can.
So, animals are conscious beings, capable of understanding cause-and-effect relationships, forming abstract thoughts, solving problems, using language, making tools, exhibiting long-term memory, and showing empathy, in many cases with skills that are superior to those of humans. But more importantly, animals can comprehend when they are being abused and killed, and they feel anxiety, fear and pain, just as humans do.
Chickens can only watch as other chickens are slammed upside-down into shackles and have their throats slit. Baby elephants cry out for their mothers, who are prevented from reaching them as they are beaten in order to make them perform confusing and even painful circus tricks. Mother monkeys grieve when their babies are torn away from them in the wild, to be sold to experimenters.
It's interesting that one of the definitions of the word "human" is "sympathetic." More and more people are beginning to show that they understand why that is important.