Empathy is part of the ancestral gift, the gift of nature that ensures the survival of all things on earth. Without interconnection, we would not survive - this is the deep biological law of empathy, which is why it is embedded not only in the long strands and spirals of our DNA molecules, but also in the genetic material of elephants, gorillas, caterpillars, ants, and even the most incredible single-celled organisms.

When scientists discuss the evolutionary history of empathy, they don't go back to monkeys, birds, or even small insects like fleas or mayflies; they start with the amazing life cycle of the single-celled slime mold. When I first heard about slime molds (there are millions of them in a teaspoon of flower soil), I wasn't particularly surprised. I was more interested in exploring relationships and the connection between empathy, intimacy and self-awareness. But then I quickly became interested in it because, despite its humble origins, slime molds have many surprising ways of embodying the life-giving power of empathy and such noble “human” qualities as altruism and self-sacrifice. The slime mold starts out as a single-celled organism that feeds on bacteria and stays put as long as there is food. When the food supply dwindles, the slime mold realizes that it is in a bad situation. At this point, a primitive form of empathy takes place. By responding to a chemical signal called an exogenous hormone - there's a similar chemical signal in the human body called cyclic adenosine monophosphate - individual cells come together and then “hold hands hand in hand” and set off in search of dinner. Aggregated slime mold cells are able to move through the soil together, like a miniature tank assembled from living, movable parts. When the cluster of cells finds a safe habitat and plenty of food, the individuals at the front of the cluster die, giving up their chance to continue reproducing so that those in the back row can have plenty of food and prosper. Researchers studying slime molds - and many are studying this because the ability of these individual cells to communicate and aggregate with each other also mimics the way a human fetus develops in the womb - are convinced that the fusion of the cells is caused by a number of It's believed that the integration of cells is controlled by a number of “communication” or “socialization” genes. These genes encourage cells to bond with each other, forming a community that improves the chances of survival for the entire species. Each cell understands the needs of the other cells and responds accordingly. This response benefits not only the individual, but the community as a whole. If single-celled organisms can communicate in such an efficient manner, what kind of mutual understanding and insight must higher organisms have? Further up the evolutionary ladder, we see an unusual empathic relationship developing between ants and some caterpillars. These caterpillars have an “ant organ” that is designed to attract and communicate with ants. One of these organs is located at the end of the caterpillar's body, and when touched by the ants, they secrete a clear liquid rich in amino acids, which the ants lick up. In this way, the ants get a healthy and nutritious extra meal with minimal effort. Because this free treat is always available, the ants stay nearby, which is exactly what the caterpillar wants. Because when it comes to trouble, you can't find a more loyal and stoic friend than an ant. When the caterpillar is threatened by its insect predators, such as bumblebees, it enlists the help of ants by activating a second “ant organ”. A pair of antennae at the back of the caterpillar's head emit chemical signals that inform the ants to go on the defensive and prepare to attack the intruder. If a bumblebee stings the caterpillar, the ants will fight the enemy to the death. The caterpillar shows us an interesting primitive model of “negative” empathy. The caterpillar gives the ants the false impression that their survival depends on the fate of the caterpillar, when in fact the caterpillar needs the ants more than the ants need the caterpillar. In fact, the bumblebee didn't care about the little ants - it just wanted to feed off the fat, succulent caterpillar. But for the ants, the caterpillar's ability to communicate with them in a language they can understand, and the free food available all day long, the ants are completely overwhelmed by the caterpillar. With all these temptations, the ants willingly swore to die to protect the caterpillar.