Autism is still viewed as a mysterious condition today. The National Autistic Society describes it as 'a lifelong developmental disability that affects the way a person communicates and relates to people around them'. It hinders their making sense of the world and they find it hard to make friends or create social relationships because of an inability to understand others' feelings. Communication causes them problems as they struggle to understand the significance of metaphor, nuance, gesture, facial expressions or tones of voice. They may seem is if they are inhabiting a completely other world.  In the past 2O years of extensive research into autism, no insights have been developed to explain the full range of strange, ritualistic, self-obsessed and sometimes destructive behaviours associated with autism. I am about to put forward a theory which, for the first time does just that. It also suggests which approaches to treatment are most likely to be successful.  Furthermore, it explains the origin of many normal human gestures, feelings and emotional expressions. The theory is ethological but I can also cite support for it on biological grounds, reached totally independently and from a completely different route by neurophysiologists at the University of Maryland.  I call it the 'fish out of water' theory.

Back to the sea
The 'fish out of water' theory is that children with autism have failed to develop mammalian behavioural response patterns, so they have to rely on an earlier system of orientations.   En route from our aquatic beginnings to being land creatures we progressed from having a primitive brain (often called the reptilian brain) to a mammalian brain.
One of the greatest achievements of this evolution was the development of social life - in other words, the development of co-operation between members of the group, which afforded greater protection to the group as a whole and allowed a longer period of development for the group's young.  This, in turn, enabled more learning to take place during the lengthier maturing period, resulting in greater flexibility and potential for further evolution. The ileocortex, the last and most sophisticated part of the brain to evolve, is concerned with reasoning, thoughts, memories, planning and consciousness.
In the transition state between fish and reptiles, which subsequently allowed evolution into mammals, there was an amphibious phase. The amphibians must have had two sets of responses: those appropriate for land and those appropriate for water. The more primitive responses continued to play an important role in evolution, in many cases providing the initial behavioural response on which adaptations could be built.

Fishy features
One obvious example of fishlike behaviour, which most mammals seem to possess without learning, is swimming. Very young children show a swimming reflex up till the age of six months, at which point it is repressed to allow walking to develop.  There are some features of the human embryo and foetus that are also present in other mammals and in fish. The gill arches, for example, support breathing in a fish but go on to become the bones of the inner ear in humans. The arteries of the human embryo are at first very similar to those of fish and the human embryo also has a tail.  By stroking the sole of a 14-week-old foetus's foot with a hair; it is possible to elicit quite complex and co-ordinated movements. These include bending of the big toe and stretching of the leg - exactly the movement a fish would make if it wanted to move its pelvic fin away from something.
Interestingly, young children make a similar movement and shape with their hands when they want to be rejecting.  The ethologist Niko Tinbergen published a photograph of a very young normal child showing displeasure with his mother - hands raised in front of the head with fingers fanned out, one palm facing inwards, the other outwards and the head leaning outward.  This behaviour, typical of autistic children, can also be seen in normal children when they are under stress. I suggest this is exactly that which we would expect if the hands were fins and the child wanted to swim away.

Cross-cultural gestures
Adults, particularly from cultures given to gesticulation, often adopt a similar gesture as a non-verbal signal of disagreement during conversation. One palm is brought up to the face, palm outwards, with the head turned sideways from the other person, while the other hand makes a swift downward movement, often ending by striking a desk or some other object. The effect of these movements in water would be movement away from the speaker.  Waving is also based on the instinctive movement of fins which in water would bring us closer to someone.
While we can inhibit gesticulations if we wish and express our reactions with words, the ancient part of our brain still urges us towards some form of movement.

The evidence of REM sleep
If autism results from a baby's failure to develop mammalian behavioural response patterns, then, I suggest, the fishlike response patterns which are peripheral in a normal baby will come to the fore and provide the basis of the child's perception of reality and his place within it.
There is some evidence that the crucial mammalian patterns may be missing in autism because of a failure to program the instinctive basis of these patterns in REM sleep, as suggested by Professor Michel Jouvet.  Children with autism have primitive patterns of REM sleep compared with normal children.  If REM sleep is indeed concerned with programming mammalian instincts, this is exactly as might be expected. This is explained in detail in The Origin of Dreams.