Also Available in:

Hibernation, Migration and the Ark

A report of a year-long hibernation in a tiny marsupial raises a subject worth revisiting.


Image WikipediaCercartetus nanus (pygmy possum)
Cercartetus nanus

A recent [November 2007] news item caused a flurry of interest among creationists. It was based on an article in the German journal Naturwissenschaften (Natural Sciences), about a marsupial able to hibernate for more than a year.1 Several people wrote in alerting us to the report. They were presumably keen for us to use it as evidence that ‘animals could have hibernated during the year of the Flood’.

It’s worth exploring just how this does or does not add to the apologetic2 arguments about the feasibility of the Flood account. First, some more detail on the report.

The discovery

The animal concerned was the pygmy possum, Cercartetus nanus, a marsupial. This is an ‘opportunistic non-seasonal hibernator’. In the right circumstances, it is able to put on substantial fat reserves which enable it to go into prolonged torpor. The research in this instance was directed to seeing whether the pygmy possum, given the right conditions, would be able to prolong its hibernation, existing only on its own body fat, well beyond winter.

The outcome was impressive—the prolonged hibernation lasted 310 days on average in various of the creatures, with one reaching 367 days.

How it might relate to the Flood account

On the surface, it seems somewhat obvious. Faced with the problem of caring for thousands of animals for a year, it would make things far simpler if the animals went into some sort of prolonged shutdown for most of the journey.

For one thing, it would dramatically reduce the amount of food and water required. For example, in the case of the pygmy possum mentioned above, the average energy expenditure during hibernation was reduced to about 2.5% of normal. This in turn drives the waste load way down, too.

For another, one can imagine the fear and restlessness among all those animals, confined in dark quarters for months while the ship was subject to all manner of ‘boat-rocking’ external forces, despite the demonstrated high stability of its proportions. Not to mention the sound of driving rain for days on end—and presumably wind, waves, and thunder, too.

It’s not surprising, then, that as far back as the classic The Genesis Flood, creationist authors have been suggesting that the animals may have entered a state of prolonged hibernation. This suggestion is perfectly reasonable, and the possibility is not being questioned here. But to point to some present-day hibernation feat as evidence supporting the Flood account is not as simple and straightforward as a quick glance might suggest.

Note that even without hibernation of any sort, the Ark journey still ‘works’, despite being a lot more problematic for its inhabitants. This is reinforced by the detailed figures and rigorous arguments in Woodmorappe’s classic work, Noah’s Ark: a feasibility study. In short, raising the issue of hibernation for apologetic purposes is not so much a crucial necessity as it is a helpful nicety.

Reducing the need for miracles

In pointing to such things as present-day hibernation, in fact in all such ‘Ark feasibility’ studies, one is really trying to minimize the need for supernaturalism, to try to explain it naturally without the need for a miracle. This is an understandable goal, to want to avoid multiplying the number of miracles required in some arbitrary fashion.

Image WikipediaHumpback whale

That is not to be confused with bowing to naturalism and liberal theology in denying the miraculous in Scripture. The description of the Flood/Ark in Genesis reinforces what Henry Morris has called the ‘economy of miracle’ seen in the Bible in general. God could, for instance, easily have suspended all the animals and Noah’s family above the clouds during the year of the Flood. But He chose to use natural laws such as the principles of buoyancy involved in a floating ship. Even then, He could have materialized a readymade Ark of safety, but instead chose to give detailed instructions for its presumably long and laborious construction.

The absence of a flurry of capricious, ‘abracadabra-style’ miracles in the Bible (apocryphal gospels have an abundance of these) is actually one hallmark of its authenticity. It makes the rare, special-purpose miracle, like raising Lazarus from the dead, or feeding the five thousand, stand out all the more. This is in part why we feel more comfortable when we have a ‘naturalistic’ explanation for an Ark-feasibility problem, as per Woodmorappe’s book. Having to postulate miracle after miracle, especially ones the Bible does not mention, would seem awkward and would in practice make the Bible account less believable to sceptics.

Clearly, having the animals go to sleep makes the journey far less problematic. What is being discussed here is the appeal to existing ‘natural instincts’, as part of this drive to minimize the supernatural.

Migration—a parallel to hibernation

Creation apologists, dealing with the issue of the animals travelling to the Ark, have similarly sought naturalistic explanations where possible. They often point to ‘the migration instincts in various animals’, and/or their instinct to travel to safety if there is impending danger. But both here and in the case of hibernation, the appeal to existing instincts is problematic. As we will see, it cannot avoid the need for the miraculous, pure and simple—and in substantial doses, in fact.

First, present-day migration instincts are nowhere near universal among animals. So even if God may have used the existing instinct somehow in some species, that still leaves the overwhelming majority of those that needed to be on board, which show little trace of a migration instinct. So if supernatural action is needed for that majority, why not the lot? How much, then, has the ‘instinct’ argument really helped the ‘explanation’?

Second, existing instincts do not direct animals towards a man-made boat.

Third, even if all animals had a migratory instinct, and even if all were programmed to migrate towards large man-made vessels, why did only those particular ones from each type make the journey?3 

Clearly, a mighty miracle was involved. We correctly talk of Noah taking the various creatures on board, but it should not be overlooked that these were ones which God sent (Genesis 6:20). Noah did not have to roam the world with lassoes and animal traps. In fact, the sight of pairs of animals migrating to the Ark would likely have been an awesome testimony to onlookers that the hand of the miracle-working creator God was here to be seen—notwithstanding the fact that hearts remained hard.

Often the argument is worded such that God could have ‘modified existing migratory instincts’ in certain creatures. OK, He could have done that, and we’re not told either way. But it’s clear from the earlier discussion that in any case, many animals would have needed to have such instincts specially created at the time. And those that already had them needed them extensively reprogrammed—and then only in those chosen for this journey. The degree of supernatural specificity is so extensive that bringing up the argument in this way seems, on analysis, to be of little help. Why not accept that God directly and supernaturally commanded the animals He wanted to travel to (and board) the Ark to do so? In short, pointing to some migratory instincts to attempt to make the account more feasible is not exactly an apologetic ‘coup’. It does not avoid or in any tangible way mitigate the need for supernaturalism, despite perhaps giving such an impression.

Back to hibernation

We similarly see creationists claim that God ‘could have used or modified existing hibernation instincts’. But here, too, we cannot escape from the raw fact that to put all those animals to ‘sleep’ for the year of the Flood would have involved a substantial dose of supernaturalism. Many mammals do hibernate each year, often for about six months at a time. (Even hibernating for half the journey would help, of course.) But many animals do not hibernate at all. So why should those on the Ark hibernate, and why at that particular time? Here, too, it is almost redundant to talk of ‘modifying existing instincts’, since it might have been just as much trouble for God to put the animals directly into a torpid state.

Then of course there is the issue of whether, even when put to sleep by God, most of the animals could have had sufficient fat reserves to last them for a year without further supernatural help. This is possibly why the observation concerning the pygmy possum stirred some interest. If some animals can be induced to hibernate for up to a year or more without running out of ‘body fuel’, then maybe this could be true for all? But the pygmy possum is already programmed to hibernate, and more importantly in this context, is designed with the capacity to ‘fatten up’ adequately in anticipation of extended periods without food or drink. Presumably, those creatures which do not hibernate would once again require special intervention to ‘fatten up’ to the extent needed in anticipation of a year-long journey.

So here, again, one might ask, ‘Why not just go straight to the obvious? God did it supernaturally.’ We are not talking about ‘any old god’ here, but about the God of Genesis, who created a complex universe (including all of its contained migration and hibernation instincts) in six earth-rotation days in the first place. Though His normal operation in the world today is via what modern science describes as the physical laws, He is certainly not constrained by them. He has described instances in the Bible in which He has overridden (or perhaps better, added to) them, for special purposes at special times in history (see also Miracles and Science). And the Flood certainly was an incredibly special time.

Summary and conclusion

Copyright Miro SchaapSome animals have extraordinary abilities and instincts to migrate. But how much does it help in defending the Flood account?
Some animals have extraordinary abilities and instincts to migrate. But how much does it help in defending the Flood account?

The Flood, almost by definition, would have required a mixture of natural and supernatural activity—both for its causes and particularly for the survival of the Ark and its crew. In the understandable tendency to seek ‘natural’ explanations wherever possible, one can easily overlook the fact that most animals would not normally and naturally either head off to and then board the Ark, or go to ‘sleep’ once there, let alone have already stored up enough fat for all or most of the journey. To talk of God ‘modifying’ certain instincts (whether migration or hibernation) overlooks/sidesteps the fact that not all animals have those instincts. And for those which do, the degree of specificity and complexity involved in the necessary ‘reprogramming’ would seem to make the existence of any previous instincts almost superfluous.

The appeal to existing instincts therefore falls somewhat short of a robust explanation. If one makes that appeal in a way that gives the impression that these mechanisms can be conveniently conscripted in a ‘naturalistic’ fashion, one risks using it largely as rhetorical window-dressing.

One needs to remember that the instincts in today’s creatures are in any case there as a result of supernatural programming during Creation Week (see Intriguing instincts). So, notwithstanding all the caveats in this article, it would still seem reasonable to point to these present-day instincts in a discussion on Flood issues. Provided, that is, that one does so as mere analogy to what was required during the Flood, rather than giving the impression that a naturalistic ‘blanket solution’ has been provided.

Published: 12 December 2007


  1. Fritz Geiser, ‘Yearlong hibernation in a marsupial mammal’, Naturwissenschaften 94(11):941–944 November 2007. Return to Text.
  2. Used in the sense of defending the faith (specifically the trustworthiness of the Bible); from the Greek απολογία (apologia), as in 1 Peter 3:15. See Christian Apologetics Q&A. Return to Text.
  3. Presumably not many would postulate that all animals around the world were sent to Noah for his selection; the most reasonable inference from the Genesis account by far is that only those intended for the journey were compelled to make the trip to the boat. Return to Text.

Helpful Resources