Dirk Jan Willem Meijers MSc 
Biology & Oceanography
Projectmanager General Sciences Zuyderzee College (retired)

Member of International Society for Biosemiotic Studies ISBS.
Cartoonist
Chauffeur of disabeld people transport
email: meijers@shoreline-man.name
Copyright: D.J.W. Meijers 2010

Abstract In 1960 Sir Alister Hardy posed the question "Was Man more aquatic in the past?"
To honour Hardy this paper discusses swimming and diving skills of human babies as possible leftover of a littoral past in human ancestral evolution.
It might be related to an ethological sensible period activating innate reflexes linked to aquatic behaviour early in life.
To my knowledge aquatic development of human babies and toddlers has not been reported in ethological sense before in literature.
Examples of ‘aquatic behaviour’ in human infants were already mentioned a few centuries ago.

After introduction of baby swimming courses and water deliveries in many countries it received a lot more attention.
In 1937, Myrtle McGraw described swimming behaviour.
Since then always was reported that repeated exposure to water activated inborn reflexes during a sensible period producing 'waterproof' babies.
These aquatic reflexes are fully functional before babies and toddlers can walk.
From early childhood to maturity all Homo sapiens can swim and dive.
It contradicts the common idea that human ancestors left forests for open plain and evolved into long distance bipedal walkers and runners.
Perhaps it is possible that aquatic properties of newborn babies and toddlers are neotenic and paedomorphic in humans, a heritage of our ancestors.

Key words
Alister Hardy, Homo sapiens; evolution; ancestors; littoral; semi-aquatic; adaptation; ethology; imprinting; sensible period;
newborns; history; babies; toddlers; baby swimming; aquatic reflexes; water babies; imprinting; water birth; neoteny; paedomorphosis.

 Introduction
After baby swimming courses worldwide it became clear that in the few first months after birth, human babies and toddlers learn easy to dive,
swim and float based on a set of innate reflexes. In ethology and neuropsychology are several adaptive time frames defined as
'critical' or 'sensitive' for imprinting. 
Those innate processes were first described of birds and later mammals, including our own species Homo sapiens.
There is now more knowledge about neonatal neurobehavioral organization for healthy full-term infants 4 and that presents a link with ethology. 
In human babies it does encompass diving, breathing control, early swimming movements, and floating. 
In all later developmental stages – up to adult humans – swimming, diving, playing in and near water is natural behaviour.

I suggest the following hypothesis:

By displaying naturally diving, floating and swimming human babies and toddlers proof being able to adapt to water the few first months after birth. 
This is imprinted in a sensitive period that activates an innate set of reflexes.

This article is based on information of numerous baby swimming courses: training sessions, correspondence, extensive available literature, photographs and film footage.
A set of supplements is available: HTML package

Real baby swimming
Water adapted newborns  were noticed already in the 18th century as mentioned by Odent and Johnson²⁶:

In the 1930’s Myrtle McGraw ^{6 21 22} did show that babies could in being startled learn how to stay afloat by adapting the involved movements. 
The data did suggest how cortical control emerges gradually, affording infants increased awareness of and control over actions. 
Eyewitnesses nowadays still report young indigenous children swimming and diving in the Amazonas, on Andaman and Nicobar islands and in boat-dwelling,
fishing and foraging sea nomad communities found in territories of five Southeast Asian states, Myanmar, Thailand, Malaysia, Indonesia and the Philippines. 
These groups have several features in common. 
In New Scientist Helen Phillips²⁹ stated remarks by Erica Schagatay about observations on physiological properties of Indonesian Sea Dwellers:

One outcome was an original approach in BirthLight baby swimming inspired by Amazonian forest people.  
Founder Françoise Freedman¹⁰ was in the nineteen seventies doing fieldwork on the upper Amazon and noticed how much fun
they had everyday with babies and children playing in rivers. 
Babies were trained to hold on to parents and swim towards them, always picked up before they got distressed.
BirthLight Baby swimming is a model accepted in all industrialised societies and swimming and diving babies are now called water babies.  
Reported sightings of natural water births in sea people societies are becoming exceptional nowadays because their ways of life are diminishing.

Waterbirth of human babies was in the 1970s propagated and accepted in Western societies. 
Experience became available with work of Michel Odent²⁷. These water births appeared remarkably safe and peaceful.
 

Reflexes in newborn and young babies
As described by Freedman¹⁰  accustoming very young newborns and babies to swimming and diving succeeded earlier and easier than expected. 
Increasing safety against drowning was a result because partaking parents learned to realise risks for little children not realised before.

The basic reflexes are recognised in almost all ‘starters’:

1.  Breath holding
2.  Lizard’ like swimming movement
3.  Legs moving to turn and
4.  Surfacing
5.  (Secondary) always open eyed

Ethologically it is comparable to normal interactions of babies, mothers, fathers, brothers and sisters. 
Important are differences in acceptance of adaptive reflexes in newborns: are babies ‘only subjects’ that can train anyway,
or is it an innate resource of newborns to adapt to aquatic behaviour?

The reflexes were already related to physiology and neurobehavioral development and McGraw’s conclusions started further research in development ³³:

McGraw described three-phases of babies in water, all documented on film.  This shows clearly early childhood development,
pertained to psychomotor abilities.  She called this “swimming reflexively” ^{21 22}.  The classification of phases is depicted in a drawing (fig.  3) ²². 
Original film footage still is available where the basic movement is envisioned (fig 5).

Three phases a, b and c are visible.  If c is really “voluntary” remains not fully accepted.  In my view it is activation of locomotive innate properties and once started lead to more. 
With 1, 2, 3 and 4 added we see something that is also recognized in the film “Drowning prevention strategy for infants and young children”
(fig.  6) ISR ^17b. 

“Only” reflective and not voluntary is not useful here.  Maybe an available innate property of babies is a better definition.
Discussions about baby swimming resulting in really sound toddlers and little child swimmers are important. 
Langendorfer and Bruya¹⁹ mention it explicitly and point to (two) different views and consequences. 
An example are Committee Sports Medicine and Fitness & Committee Injury and Poison organisations (SMF and IP)
warning that it is not the case ⁵, a reason for YMCA of USA national organization to publish their disagreement in Pediatrics Letters to the editor ¹¹.

Committee Sports Medicine and Fitness & Committee Injury and Poison (SMF and IP)⁵:

YMCA USA11:

SMF and IP⁵ are fixed on swimming abilities only. They judge four years as acceptable starting point. 
YMCA ¹¹ takes into account the difference between ‘formal swimming lessons’ and baby swimming activities. 
The purpose of baby and toddler courses is not purely ‘swimming’ but realising water safe behaviour early in the first year. 
Langendorfer and Bruya ¹⁹ seem to take sides with SMF IP.  Baby swimming training is okay, but very early starts are not. 
They warn to overestimate a very early start as McGraw with her twins. 
A point is, that recently (2010) the position of the two opinions is changing. 
The reasoning of the YMCA and other mentioned positive baby swimming organisations is more accepted. 

To show this I add now (2011) more to illustrate the change: OK_to_Teach_Toddlers_to_Swim

Critical or sensitive imprinting period
In ethology imprinting was introduced in research on animal behaviour. 
It was based on recognising innate aspects of behavioural traits, developing in critical (fixed) or sensible (flexible) time frames. 
It started with birds and established itself next in research on mammals.  Concepts were learning strategies and a host of
social behavioural interactive processes in H.  sapiens were mentioned by Eibl-Eibesfeldt ^{8 9}.
A problem was and in a sense still is  ‘tabula rasa’ ^{18 35} for human development described by John Locke (1632 – 1704):

This ‘tabula rasa’ still is accepted for our little babies.  But ‘a variety of faculties to receive and abilities to manipulate
or process the content’ as Knezek18 describes, it resembles innate imprinting possibilities (Meijers) in sensitive periods. 
Reported most for humans is language adapting.   A problem there exists in different opinions, shown by Johnson and Newport (1989),
cited in Purves ET al. ³⁰:

As far as language is concerned, the process begins earlier than three years.  The first year is more accepted but does not mean ‘language’. 
The essential language-imprinting phase is a long 'critical period'  (fig.  4) but for baby swimming we have to do with a very short 'sensible period'. 
Able swimming can  still be realized years later but it takes grownups a lot more time to achieve results. 
The discussion between SMF IP and YMCA in Pediatrics ^{5 11} shows something similar, connected with time lags for aquatic adaptations at different ages.
The YMCA and Infant Swimming Resource (ISR) look at little babies able surviving  to stay afloat at an age younger than one year and mention success in one to six months.
The SMF and IP Committees defend real swimming abilities and choose two to four years of age as starting point for training and state that 55 to 58 month are needed
to complete this process, in fact a year or more. 
It shows that there should be cooperation and more research to overcome conclusions that differ until now substantially.
ISR Harvey Barnett presented his considerations in  ‘A Behavioral Approach to Pediatric Drowning Prevention’ at University of Oklahoma Health Science Centre, March 5 2009 ³. 
The question to uncover apparent reflexes of very young children adapting to aquatic circumstances absolutely differs to that about two to four years old children. 
The early starting point shows quick and easy aquatic adaptation of newborns and toddlers. 
Barnett stated ike others that such development is connected to early psychomotor abilities.

Aquatic imprinting of babies
Success of baby swimming is real and connected to imprinting in a sensitive period. 
It is based on innate possibilities in first months to one year after birth.  Even when submerged they are stimulated by interacting parents (or trainers). 
Missing early imprinting can damage basic behaviour for many birds and mammals, our species included as stated
by Eibl-Eibesfeldt⁸ and Alcock¹.  In psychology and neuropsychology the same is mentioned and sometimes compared to ethological
definitions in biology as Balatskii ² did:

Baby swimming courses ascertain human adaptation under aquatic circumstances as an ethological preset sensitive period. 
Safe aquatic behaviour is fulfilled for young human babies if they interact with parents (including brothers, sisters and other siblings). 
It shows as result positive affectivity between children and parents.  This makes the ethological observation significant in two ways .
Missing this for older children lead to problems with learning to swim and dive. It takes more time to adjust and for a number also to overcome hydrophobia.
But it does not make swimming impossible forever. 

It differs substantially from missing the imprinting phases for developing much more complex abilities for speech and language³⁰. 
Because learning to swim and dive is obvious possible for adults later, I prefer to label the time frame shown in baby swimming as ‘sensitive’ and pertinent not ‘critical’.
The three phases described are constantly observed in baby swimming courses. 
McGraw did so when exposing her boys very young, but the start is still early at four to six months. 
The reason to start later is generally linked to the baby's immune system that is not fully developed until about six months. 
Earlier start could be real in ‘primitive’, not dense populations where mothers are passing immunoglobulin antibodies by breastfeeding
in a substantial longer phase, sometimes even for more years. Statements about starting aquatic activities with babies mention
first swimming ‘lizard like’ ²¹ as shown in fig.  3 and fig 5.
Then rotating legs in one direction and popping-up floating in a position on their back as if wearing a life jacket.
Some of the reported movements in testing very young babies in water were ethological described earlier by Eibl-Eibesfedt ⁸,
but not explicit as ‘aquatic’ trait:

The swimming movements are elicited when Johnny was exposed to water, one of the twins Johnny and Jimmy of Myrtle McGraw, 11 days old ²¹. 
A lizard-swimming fragment of a mechanical simulation of salamander locomotion14 was recently added to the film about Johnny ^17a.
The ‘floating effect’ is described on a diversity of sites about baby swimming. 
A good and even important example is “Miles story, Drowning prevention strategy for infants and young children”; a film published by ISR ^{3 17b}. 
The baby had 3 weeks of ISR lessons prior to having his simulated fully clothed self-rescue videotaped.  Fig.  6 shows a baby turning upward (see also 7b).

It depicts what McGraw described (fig.  3, 1-2-3-4): submerged, they hold in their breath and start with swimming motions (fig.  7a).
 They show a rotation (fig.  7b).  Floating on back, face above water, they start breathing and rather relaxed crying and babbling (fig.  7c).

 a

 
  b

 c

Fig.  7.  Three stages © DJW Meijers 2009

The sensitive period of our species ends after a start at four to six months in about a year. 
It reveals the outcome of a genetically preset sensitive (sensible) period for imprinting with an important role of partaking parents.  
But accepting ‘we’ have ‘instinctive’ behavior and beyond this ‘innate imprinted’ learning phases as newborns is still hotly debated.
In my view the link neuropsychology picked up with original definitions of imprint in ethology for humans is positive. 
It shows a lot more open mindedness about the H.  sapiens position between other mammals. 
Palmer²⁸ pointing at the role of this imprinting in ‘Bonding Matters, The Chemistry of Attachment’ mentions the situation
that still needs improvement:

In “Water babies” of Freedman ¹⁰ the work of Liselott Diem ⁷ in the 1970's is mentioned.  The same goes for baby-swimming organisations in many different countries. 
What was shown in systematic testing kindergarten children between 1974 to 1976 by Liselott Diem and students of Cologne Sports High School in Germany is,
that interaction with parents and peers does more. 
Learning to swim at an early age demonstrated advanced development in motor skills, reaction time (reflexes) and concentration (focus). 
But than extra positive evidence was found of social interaction, self-confidence, independence and coping with new unfamiliar situations. 
Overall, children were better adjusted than their peers who had not participated in early swimming programs. 
Increase in both self-esteem and independence due to baby swimming were cited as contributory factors.
It confirmed that children started swimming at an early age benefited of positive interaction and bonding with parents. 
As Federal Minister for Education and Science she therefore propagated swimming for babies and teaching movement and gymnastics for pre-school children and kindergartens.
Sigmundsson and Hopkins³² recently did explore the effects of baby swimming on subsequent motor abilities.
 In this study also a group of baby swimming active children (2 – 4 month old) was compared with a group that had not this experience. 
It again repeats results of McGraw and Diem, and shows a correct view about stimulating aquatic activities with babies and toddlers they note in the following key messages:
 

• Physical exercise facilitates the development of motor skill
• Baby swimming programmed may have positive effects on motor skill development
• Baby swimming programmed targets activities promoting eye–hand coordination and  the provision of vestibular stimulation
• Baby swimming may have rather specific effects in the motor domain, its potential  positive benefits should also be explored in
other areas of relevance for child  development What  described by Bell et. al. 

in “Concept clarification of neonatal neurobehavioural organization” ⁴  again is similar:

Ethology fits to al described interactions and is recognized ultimately in ‘Myrtle McGraw's “Unrecognized Conceptual Contribution to Developmental Psychology’ of Gottlieb¹²:

Neoteny and paedomorphosis
 Not connected with concepts of neoteny and paedomorphis the hypothesis about aquatic adapting of newborns has no sense. 
Aquatic adaptation of newborn H.  sapiens can be linked  to ancestral “predestinations” we carry. 
In developmental biology these are phylogenetic characters in species revealed in adults that retain traits previously seen only in juveniles. 
Lorenz ²⁰, Morris²⁴ and Gould¹³   described this for different animals, humans as well.  
It is not the place to go into this, but more is available: info@shoreline-man. name).

 The aspect of human newborns in water reminds to these neotenic developmental properties described by Lorenz ²⁰, Morris²⁴ and Gould¹³. 
Lorenz description of neoteny is significant: he defined neotenic in combination with paedomorphic retention of (foetal and) juvenile characters into adult life
as link to possible original ancestral properties¹³. 
According to Lorenz they can be connected to possible ancestral anthropoid (pre-human) apes.
If aquatic adaptive behaviour in our species is comparable to Lorenz' definition of neoteny, than it is allowed to connect with ancestral characters. 
Accepting that, early human ancestors could have undergone forced adaptation in restricted sets of habitats leading to aquatic morphological and behavioural properties. 
Swimming, diving, playing in and near the water is important natural behavior of all human stages as Niemitz²⁵ described. 
Not only for playing but also foraging, dispersing, transporting and travelling.
Views are changing and carefully open those possible probabilities like mentioned in Wrangham et al³⁶.

(*USO’s: aquatic or semi-aquatic underground storage organs of plants (Meijers)).

 Conclusion Newborns and little children aquatically adapt very quick. 
Physiological properties encompass diving, controlling breath, early swimming movements and floating. 
Acting of babies after submerging and floating are based on genetic traits activated in an ethological defined sensitive period. 
It means that the formulated hypothesis seems acceptable:

By displaying naturally diving, floating and swimming human babies and toddlers proof being able to adapt to water the few first months after birth. 
This is imprinted in a sensitive period that activates an innate set of reflexes.

A series of inbuilt reflexes has to be triggered in a genetic preset sensitive (sensible) period that last four or six months to one year. 
Parental individuals are needed to fulfil the process.  This implements aquatic developmental aquatic dynamics early in life.

The reflexes observed are:

1.  Controlling breath when submerged can be accepted as adequate reflex.
2.  To swim in ‘Lizard fashion’ is a reflex.
3.  After being submerged turning up and resume a floating position, head up with arms and legs spread complement a possible
     innate series of reflexes.
4.  Active interaction with parents (and other relatives) strengthens the functioning of these reflexes.
5.  If realised in an innate sensitive period of the first four or six months to one year, the young baby can become “waterproof”.

Waterproof ‘reflexes’ of newborns are an essential unique feature of our species, not observed in other great apes (genus Pan, genus Gorilla and genus Pongo).  
In al later stages of development up to pubertal and adult maturity,
humans show physiological and morphological talented swimming, diving, playing in and near the water as natural behaviour. 
Baby swimming gives as well social interaction, self-confidence, independence and coping with new unfamiliar situations.
This development is connected to psychomotor and social abilities in the first year after birth.  It contributes to the debate about a possible semi-aquatic start of early
human ancestors. 
Aquatic properties of newborns probably have a neotenic and paedomorphic connection with ancestrally properties. 
If accepted it seriously pinpoints a semi-aquatic habitat as possible
evolutionary route for early human ancestors.

If they in first setting were only adapted to bipedalism after leaving woods it does not correspond with young that are their first year impossibly able to walk and cling to mothers. 
It lacks totally biological coherence with the aquatic adaptations shown by newborns and toddlers.
On the contrary yet, it absolutely makes sense with a paleontological starting point in semi aquatic habitats leading to adapted aquatic babies (fig.  9. ).
It failed me to find anything in paleoanthropology or genetics as well to make it obvious or absolutely impossible. 
Fossilized baby leftovers are very rare and it seriously is not to expect paleontological that will proof I am wrong or right.
My argumentation can only be based on living, fleshy very young  - and adult - H.  sapiens. 
It does seriously defends the idea of Sir Alister Hardy as he published it in 1960, as “Was man more aquatic in the past”¹⁵ and strengthens the view of Elaine Morgan²³
in The Descent of Woman:

Discussion Important point is the ‘floating’ reflex that is problematic when babies and little children are not brought in contact with water the first four to six months
to one year after birth. 
Reason is missing the mentioned sensitive imprinting period. Then drowning of little children can be a real danger as Eibl-Eibesfeldt mentioned ⁷. 
Young babies and toddlers easy adapt to water in a few weeks. 
It means lesser fear in presence of parents and reacting naturally to diving and swimming. 
Because training babies in swimming pools only started recently, possible strengthening of reflexive adaptations were not fully recognized and a completed ethological
interpretation was lacking. It creates controversies about importance of baby and toddler swimming to realize very young efficient swimmers. 
Better safe swimmers are generally not to be expected at more than four years.  But ‘natural’ early learning does exist as long as our species itself
and most probable even much longer than that.

Many children in extensive societies started in discrepancy for ages not or considerably later with swimming lessons and did not adapt easy or not at all: 
Some never learned it and even a lot of adults, even seamen, were unable to swim. 
That is a serious reason to justify baby swimming as valuable activity everywhere. 
NOT to defend that babyswimming courses deliver guaranteed ‘safe’ swimmers and divers, but only to find out if there exists indeed a quicker adaptation. 
It is a challenge because it invites to an efficient research on differences between time lags for different age groups.
A second point is to gather ethological aquatic adaptations in other Mammalia species to find out if human newborns really are exceptional. 
Examples resemble to semi-aquatic Otter (Lutra spec. ) and Polar Bear (Ursus maritimus).
Most examples I know do not have the distinct combination of  ‘not walking’ but ‘able swimming’ period. 
I did not find any reporting of young 'baby' Hominidae showing the same aquatic abilities assisted by their parents as does H.  sapiens.
In a sense of course there are anyway numerous variations of physical possibilities of H.  sapiens as Eibl-Eibesfeldt⁸ cited Konrad Lorenz:

Added are in html some examples of baby swimming activities. 
Also videotaped ethological resembling phenomena and aquatic activities of other animals are presented with comment:
Otter with baby, Sea lion with baby, Elephant swimming with David Attenborough, Tapirs enjoying a swim and a Penguin adopting to water in a zoo.

Ask ( info@shoreline-man. name )

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