Wednesday, February 3, 2016

Comparing Animals and Humans: Blindness and Echolocation

We often place ourselves at the apex of evolution and view ourselves, humans, as unique creatures against which all other species are found wanting.  The result of this perspective is smugly satisfying, but it causes us to miss the rich and complex lives that other animals around us are living, and to denigrate their actions based on emotion or intelligent reasoning as being merely instinctual.  Carl Safina wishes to disabuse us of such fantasies in his book Beyond Words: What Animals Think and Feel.  He uses detailed studies of the lives of elephants, wolves, killer whales, and dolphins, coupled with an amazing collection of anecdotal experiences to convince us that we are more similar to other animals than we might wish to believe.  Or, if one prefers, he convinces us that animals are similar to us.

Safina’s constant message is that we will learn more about other species and more about ourselves if we focus more on the similarities and less on the differences.

“If you imagine the very slow changes over millions of years that turned some mammals into apes and others into whales, we seem to have grown very distant indeed, almost estranged.  But is that really a long time, or a big difference?  Take the skin off, and the muscles are much the same, the skeletal construction nearly identical.  The brain cells, under a microscope, are impossible to distinguish.  If you imagine the process very much sped up, you see something real: dolphins and humans, both having already shared a long history as animals, vertebrates, and mammals—same bones and organs doing the same job, same placenta and that same warm milk—are basically the same, in merely shape-shifted proportions.  It’s a little like one person outfitted for hiking and another for scuba diving.”

“Whales are nearly identical to us in every way except their outer contours.  Even their hand bones are identical to ours, just shaped a little differently and hidden in mittens.  And dolphins still use those hidden hands for handlike gestures of touch and calming reassurance.  (In any group of spinner dolphins, at any given time one-third are usually caressing with flippers or making bodily contact, a bit like primates grooming.)”

Even our human brains, of which we are so proud, are quite similar in structure and function to that of other animals.

“If you look at side-by-side drawings of human, elephant, and dolphin brains, the similarities overwhelm the differences.  We are essentially the same, merely molded by long experience into different outer shapes for coping with different outer surroundings, and wired inside for special talents and abilities.  But beneath the skin, kin.”

The misunderstanding of our common origin has produced tragic misconceptions.  For many years people believed animals could not experience pain or possessed no emotions at all, leading to horrible abuses.

“Elephants and mice might not tell us what they are thinking.  But their brains can.  Brain scans show that core emotions of sadness, happiness, rage, or fear, and motivational feelings of hunger and thirst, are generated in ‘deep and very ancient circuits of the brain,’ says the noted neurologist Jaak Panksepp.”

“Rage, for example, gets produced in the same parts of the brains of a cat and a human.”

“Under stress, other animals’ blood carries the same hormones that the blood of stressed-out humans does.”

And our emotions are also associated with the same chemical drivers.

“Complex animals have inherited very ancient emotional systems.  The genes that direct our own bodies to create the mood-making brain hormones oxytocin and vasopressin, for instance, date back at least seven hundred million years.  They ‘likely arose when animals became mobile and started to make experience-based decisions’.”

Emotions that we take for granted as being genetic in origin are, but the activation is via the programmed release of hormones and other chemicals.  What we describe as “maternal instinct,” and the much less potent “paternal instinct,” are chemically aroused states.  And the mechanisms that generate them are shared with other animals.

“Oxytocin drives bonding, and it makes elephants and many other species act social or sexual.  Block the hormone; many mammals and birds lose interest in socializing, pairing, nesting, and contact.  Oxytocin and opiod hormones create sensations of pleasure and social comfort in many species, including humans.”

New mothers are doused in oxytocin to encourage them to care for their infant.  It isn’t possible to determine what would happen if mothers were deprived of the chemical.  However, fathers evolved in such a way that oxytocin levels are naturally low.  It is ethical to experiment with men whose oxytocin levels are artificially increased.

“Given a sniff of oxytocin, human fathers get more playful with their babies, increase eye-to-eye gazing, and show greater interest in the child.  This is the chemistry of bonding.”

Safina goes to great lengths to demonstrate the lives of the animals he has studied mirror in many ways the lives of humans in terms of both intellectual and emotional drivers.  He reaches a firm conclusion: animals are not “its” they are “whos.”  Each member of a species is a unique individual.

“’Who’ animals know who they are; they know who their family and friends are.  They make strategic alliances and cope with chronic rivalries.  They aspire to higher rank and wait for their chance to challenge the existing order.  Their status affects their offspring’s prospects.  Their life follows the arc of a career.  Personal relationships define them.  Sound familiar?  Of course.  ‘They’ includes us.  But a vivid, familiar life is not the domain of humans alone.”

Safina succeeds in demonstrating the connection between humans and other animals, mostly by describing animal behaviors that we can recognize as familiar to humans.  However, he also provides a fascinating example of how the human-animal similarity can be demonstrated in human activities.

Consider dolphins.  Like many sea animals they must live in a world where light makes visualization important.  However, they must also live at depths where light does not penetrate and they must resort to sound to navigate.  They produce bursts of sound and sample the reflected waves: echolocation.

“Dolphins using sonar can detect a ping-pong ball one hundred yards away, a distance at which many humans would fail to see it.  They can track rapidly swimming fish well enough to capture them, meanwhile avoiding obstacles while travelling at high speeds.  They click fast: each click last ten millionths of a second, and they make up to four hundred clicks per second.”

Dolphins evolved this capability by adapting the same basic brain structure that they share with humans.  Eyes do not capture images and pass them on to the brain.  They are sensors that respond to perceived energy signals.  These sensations are passed on to the brain where very complex logic is used to construct an image from them.  Could it be that this same logic can be used to interpret sonic signals?  And could humans learn to use it in that manner?

Safina introduces us to Daniel Kish

“Perhaps the most amazing practitioner of echolocation among humans is Daniel Kish, blind since he was one year old, who early in life discovered that making clicking noises helped him get around.  Much of his brain must be reassigned to sound, because he uses his own clicks to navigate.  He can ride a bicycle in traffic (hard to imagine), and he has founded World Access for the Blind to teach other blind people to use their own sonar—to summon, as it were, their inner dolphin.”

Kish can’t compete with a dolphin. He would have to develop a more powerful and more rapid sonar system to acquire greater accuracy and function at larger distances, but what he can do is still astonishing.

“Sounds from his tongue clicks, he explains, ‘bounce off surfaces all around and return to my ears as faint echoes.  My brain processes the echoes into dynamic images….I construct a three-dimensional image of my surroundings for hundreds of feet in every direction.  Up close, I can detect a pole an inch thick.  At fifteen feet I recognize cars and bushes.  Houses come into focus at about 150 feet’….’Many students are surprised at how quickly results come.  I believe echolocation capability is latent within us….The neural hardware seems to be there; I’ve developed ways to activate it.  Vision isn’t in the eyes; it’s in the mind’.”

Perhaps we could learn more from our animal relatives if we would stop trying to render them all extinct.  Safina provides an apt summary for the discussion of ourselves and our cousins.

“There is no other animal like us.  But don’t forget, there are no other animals like each of them, either.”

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