Linley Sambourne’s cartoon ‘Man is but a Worm’, appearing in Punch in 1882 in depicts the evolution of man; from worm, to ape, to an archetypal top-hatted Victorian gentleman, concluding with an image that had fast become an emblem for evolutionary theory – the bearded Darwin himself. The cartoon ridicules the idea of a relation between the two species, using grotesque caricature to depict Darwin’s theory as nothing more than comical absurdity.
Like Linley Sambourne’s cartoon, Charles Kingsley’s The Water Babies parodies much of the discourse surrounding the origins debate. However, Kingsley does not choose to satirise the theory of natural selection itself, instead Kingsley parodies the reaction Darwin’s ideas provoked. The novel ‘argues against purely physical definitions of humanity’.  Kingsley takes a bone of contention in the origins debate, The Great Hippocampus Question (which debated upon the similarities between the anatomy of apes and men) and lampoons the debate as ‘the great hippopotamus debate’, using humour to emphasis the absurdity of reducing humanity to anatomy.
‘You may think that there are other more important differences between you and an ape, such as being able to speak… and knowing right from wrong and saying your prayers; but that is a child’s fancy my dear…if a hippopotamus major is ever discovered in one single ape’s brain nothing will save your great-great-great-great-great-greater-greatest-grandmother from having been an ape too.’
Rather than ridicule the idea of natural selection Kingsley takes the essence of the theory and transforms it into what he terms ‘Fairy Science’. As Anne Chassagnol notes:
‘Darwin’s theory is quite a fairy-like concept concerning as it does metamorphosis…[and] focusing frequently upon fantastical, often miniature animals including, larvae, beetles and butterflies’. 
Kingsley adopts these characteristics of science and re-imagines them as tenets of fairy-tale. Tom’s odyssey begins with his metamorphosis: like a butterfly he leaves his old husk behind and devolves into an eft in preparation for his moral evolution.
In On the Origin of Species (1859) Darwin emphasises that the natural world is characterised by a struggle for survival. He urges us to remember that ‘birds which are idly singing around us mostly live on insects and are thus constantly destroying life’ .  This struggle for survival is depicted in The Water Babies. The trout ‘gobble the beetles and leeches… [and swim] about with great worms hanging out of their mouths, tugging and kicking to get away’ . The otter despairs how men speared her ‘poor dead husband’ . Even Tom is described as being at the bottom of the food chain; the otter first decreeing that Tom ‘is not worth eating after all’ and then threatening that the salmon will eat him and then they will eat the salmon. This struggle is imperative to Tom’s passage into adulthood. Gradually he moves up the evolutionary ladder no longer fraternising with the gnats, the dragonflies and the sea snails, and instead talking to Ellie and other water babies.
The logical inversion of Darwin’s theory, devolution, is made a concrete possibility in The Water Babies. As Mrs Bedonebyasyoudid asserts ‘if I can turn beasts into men, I can by the same law of circumstance and selection and competition, turn men into beasts’. Tom observes many examples of this throughout his journey: some of the salmon become ill adapted through their atrophy and as a result ‘grow ugly and brown and spotted;’ the Tomtoddies turn into radishes, as their brains are so filled with water due to their preoccupation with ‘The Examiner;’ the Doasyoulikes, a race of idle humans, ‘grow so stupid … [that] they have almost forgotten how to talk… [and] will all be apes very soon’.
Tom himself is described at the beginning of the tale as a ‘little black ape’ , which immediately emphasises his risk of degeneracy. Furthermore, he is described to be quite at home in a chimney; ‘a mole underground’ he is adapting to his uncivilized surroundings, and therefore is presented as being on the wrong evolutionary tract. Kingsley uses Tom as a symbol for Victorian anxieties about the degeneration of the poor, who: unclean; uneducated and faithless seemed symptomatic of social degeneration on a national level. This connection between moral decay and evolutionary decline was unequivocally assumed, as although by the 1830s the term ‘evolution’ was used in its modern sense, prior to this it was ‘a term for individual growth’, which ‘only further helped to forge and explicit connection between the two processes’. 
Kingsley responds to the anxiety of degeneration with the concept of recapitulation, an idea which suggested that ‘the development of the individual repeats the development of the human race’. Just as ‘the human foetus passes in the womb through the evolutionary stages of life on earth … the growing child passes through physical and psychological stages of savagery and barbarism’. 
In The Water Babies the fairies spirit Tom away from London, where he is at risk of evolving into a double of Mr Grimes; he imagines that when he himself is a master ‘he would bully [his apprentices] and knock them about, just as his master did to him’ . They reduce him to an embryonic size and submerge him in a womb-like water-world, where Tom must ‘re-inhabit nature to achieve his own humanity, [in order to] transcend his origins.’  Mrs Bedonebyasyoudid embodies nature’s absolute justice; she ‘cannot help punishing people when they do wrong … [she] work[s] by machinery … wound up carefully [so that she] cannot help keep going’. She does not interfere, allowing the water babies to learn from their mistakes, and adapt accordingly.
However, her code of conduct does differ from Darwinian selection. The natural education Tom is subject to is not reliant on qualities that nurture survival, but on qualities that nurture Christian virtue. It is not survival of the fittest but survival of the moral. For example, Tom grows prickles not because he has done something contrary to his survival but because he has done something contrary to Christian morality; ‘when his soul grew all prickly with naughty tempers, his body could not help growing prickly too’. The use of the word ‘punish’ throughout the novel (the tommodites are ‘punished’ for worshipping the ‘idol’ examination, the salmon ‘properly punished’ for their slothful nature) magnifies the sense that God uses the seemingly autonomous model of natural selection to enact divine punishment. Kingsley only reconciles religion with science, by making the two entities one and the same; faith in the universal laws of science becomes synonymous with faith in divine presence.
This is made irrefutably clear at the end of the novel when Tom and Ellie learn that all the fairies who have throughout Tom’s journey governed nature’s law are one and the same. This epiphany is met with ‘a clear, white, blazing light’ emblematic of divine presence. To Kingsley ‘evolution must have meaning and purpose, two attributes that Darwin had tried to eliminate from his own theory’.  Kingsley separates the evolution of man from the evolution of all other organisms, upholding modern man as a superior being because of his moral choices. The notion of Mrs Bedonebyasyoudid’s ‘downhill as well as uphill road’ is made clear; Tom learns Christian principles, and therefore is no longer at risk of remaining a degenerate ‘little black ape,’ nor a ‘poor little heathen’, instead he journeys upon the ‘uphill road’ becoming a ‘great man of science’.
The Water Babies functions simultaneously as a tale of evolutionary recapitulation and as a religious pilgrimage. Tom’s return to a pre-human morphology allows him to spiritually as well as physically adapt to achieve a redemptive end. Parallel to this, physical evolution and moral evolution are inextricably intertwined, as Kingsley hypothesises ‘your soul makes your body just as a snail makes his shell.’ Kingsley takes the idea of evolution as a grotesque struggle and moralises it, likening each transitional stage of physical advancement with moral improvement, and moral decline with physical deterioration. Faith in the indefinite, a tenet of religious belief becomes a prerequisite for scientific practice –
‘You must not say that this cannot be, or that is contrary to nature. You do not know what nature is or what she can do’.
Overall, the Darwinian subtext present in The Water Babies is paramount to the novel’s moral sentiment, that although ‘some people say that [bad behaviour] … is nature, and only proof that we are all originally descended from beasts of prey’, ‘little boys can help it and must help it’ otherwise ‘by doing only what they liked’ they are at risk of degeneracy and ‘will all be apes very soon’.
 Kingsley, Charles, The Water Babies, (Oxford: Oxford University Press, 1995).
 Straley, Jessica, Of Beasts and Boys: Kingsley, Spencer and the Theory of Recapitulation’, Victorian Studies, Vol. 49, No. 4, (2007) pp. 587-609.
 Anne Chassangnol, ‘Darwin in Wonderland: Evolution, Involution and Natural Selection in The Water Babies’, University of Toulouse, France, (2010) p. 1.
 Charles Darwin, On the Origin of Species, (Oxford University, 1859) p. 62.
 Moore, K.L. and Persaud, T.V.N., The Developing Human; Clinically Oriented Embryology, Fifth Edition, (Philadelphia: 1993), p. 608.
 Joseph Green, ‘“THE GREAT FAIRY SCIENCE”: THE MARRIAGE OF NATURAL HISTORY AND FANTASY IN VICTORIAN CHILDREN’S LITERATURE’, (University of Missouri-Columbia, 2009) p. 161.