I proceed now to the consideration of Animate Bodies indued with a Sensitive Soul, called Animals. Of these I shall only make some general Observations, not curiously consider the Parts of each particular Species, save only as they serve for Instances or Examples.
First of all, because it is the great design of Providence to maintain and continue every Species, I shall take notice of the great Care and abundant Provision that is made for the securing this End. Quanta ad eam rem vis, ut in suo quaeque genere permaneat? Cic. Why can we imagine all Creatures should be made Male and Female but to this purpose? Why should there be implanted in each Sex such a vehement and inexpugnable Appetite of Copulation? Why in viviparous Animals, in the time of Gestation should the nourishment be carried to the Embryon in the Womb, which at other times goeth not that way? When the Young is brought forth, how comes all the nourishment then to be transferred from the Womb to the Breasts or Paps, leaving its former channel, the Dam at such time being for the most part Lean and Ilfavoured? Here I cannot omit one very remarkable Observation I find in Cicero. Atque ut intelligamus (saith he) nihil horum esse fortuitum, sed haec omnia providae solertisque naturae, Quae multiplices foetus procreant, ut Sues, ut Canes, his mammarum data est multitudo, quas easdem paucas habent eae bestiae quae pauca gignunt. That we may understand that none of these things (he had been speaking of) is fortuitous, but that all are the effects of provident and sagacious Nature, multiparous quadrupeds, as Dogs, as Swine, are furnished with a multitude of Paps: Whereas those Beasts which bring forth few have but a few.
That Flying Creatures of the greater sort, that is Birds should all lay Eggs, and none bring forth Live Young, is a manifest Argument of Divine Providence, designing thereby their Preservation and Security; that there might be the more plenty of them; and that neither the Birds of Prey, the Serpent, nor the Fowler should straiten their Generations too much. For if they had been Viviparous, the Burthen of their Womb, if they had brought forth any competent number at a time, had been so great and heavy, that their Wings would have failed them, and they became an easie Prey to their Enemies: Or if they had brought but one or two at a time, they would have been troubled all the Year long with Feeding their Young, or Bearing them in their Womb. * Dr. More.1
This mention of Feeding their Young puts me in mind of two or three considerable Observations referring thereto.
First, Seeing it would be for many reasons inconvenient for Birds to give Suck, and yet no less inconvenient if not destructive to the Chicken upon exclusion all of a sudden to make so great a change in its Diet, as to pass from liquid to hard Food, before the Stomach be gradually consolidated and by use strengthened and habituated to grind and concoct it, and its tender and pappy Flesh, fitted to be nourished by such strong and solid Diet; and before the Bird be by little and little accustomed to use its Bill, and gather it up, which at first it doth but very slowly and imperfectly; therefore Nature hath provided a large Yolk in every Egg; a great part whereof remaineth after the Chicken is hatch’d, and is taken up and enclosed in its Belly, and by a channel made on purpose received by degrees into the Guts, and serves instead of Milk to nourish the Chick for a considerable time; which nevertheless mean while feeds it self by the Mouth a little at a time, and gradually more and more, as it gets a perfecter Ability and Habit of gathering up its Meat, and its Stomach is strengthen’d to macerate and concoct it, and its Flesh hardened and fitted to be nourished by it.
Secondly, That Birds which feed their Young in the Nest, though in all likelyhood they have no ability of counting the number of them, should yet, (though they bring but one morsel of Meat at a time, and have not fewer (it may be) than seven or eight Young in the Nest together, which at the return of their Dams, do all at once with equal greediness, hold up their Heads and gape,) not omit or forget one of them, but feed them all; which, unless they did carefully observe, and retain in Memory which they had fed, which not, were impossible to be done; this I say, seems to me most strange and admirable, and beyond the possibility of a meer Machine to perform.
Thirdly, the marvellous speedy growth of Birds that are hatched in Nests, and fed by the Old ones there, till they be fledg’d and come almost to their full bigness; at which perfection they arrive within the short term of about one Fortnight, seems to me an Argument of Providence designing thereby their preservation, that they might not lie long in a condition exposed to the ravine of any Vermine that may find them, being utterly unable to escape or shift for themselves.