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deeper-living fish and octopuses don’t use this risky strategy, nor do most other creatures that live a mile deep.
    Biologists Janet Voight and Tony Grehan, filming a rocky outcrop rising above the muddy abyssal plain off the west coast of Canada from a submersible in 2000, made a fascinating discovery: they saw twenty-eight female octopuses (of unknown deep-water species) guarding eggs laid on the rocks. They had laid eggs in different places and each had laid fewer than 100 large eggs, attached singly to the rocks. Some of these eggs were the largest known of any octopus, about 2 in. (5 cm) long. After some of these eggs were collected, they hatched out into the largest octopus hatchlings known to science. One female was still guarding her eggs in the same location a year later, and she looked senescent the second year, much like Olive toward the end of her brooding period. Based on the rate of development of the eggs, their size, and the temperature of the water at those depths, we believe it may take up to four years for the eggs of this species to hatch, presumably guarded all the time by a fasting female octopus. At least the deep-water females don’t have as many predators to watch for as the shallow-water species do, but the brood time is remarkable. The possibility that the female doesn’t eat during such a long guarding period is something to think about, and extrapolation from the brooding time leads to a possible life span of that species of over ten years, the longest for any octopus. Everything’s slower in the deep.
    Researchers have collected developing octopus eggs and viewed themunder light with low-power microscopes or opened them up to see several stages of the development that occurs inside the egg. Huge changes take place in the egg capsule, starting with a cell and ending up with a complete and fairly well-developed animal. Since the egg capsules are usually opaque, embryologists (who study development before birth) can sometimes see what’s going on inside, but often they have to open up an egg, preserve the embryo, and study it later. The single fertilized egg cell divides into clumps of cells, arranged in blastula and then gastrula stages. Gradually these cell collections begin to specialize, and we can see the beginning of the adult organs. Meanwhile, the little embryo flips its position in the egg twice, ending up with its mantle pressed against the opposite end from the attachment, ready to push out in the world during hatching.
    When does an egg become an octopus? The changes are gradual; there’s no specific time, as in all embryological development. First, the yolk develops to nourish the embryo and can be seen extending toward the egg capsule attachment. Then the arms develop, first visible as eight arm buds around the yolk and gradually getting longer (though the planktonic octopuses like the giant Pacific octopus don’t have very long arms at birth). The eyes begin to develop at this point, and since they are dark with their pigment, anxious aquarists and the divers visiting Olive could see them through the capsule and know the eggs had been fertilized. Next, the heart begins to develop well enough to be an organ and to beat. The final part of the octopus that can be seen to develop is the chromatophores—there are not many of them and they are conspicuously large in the semitransparent skin. All through the embryonic period, the yolk is used to nourish the embryo, and by the time of hatching, none is left. Sometimes an octopus is disturbed during her brooding, and she may inadvertently push the eggs around so they hatch early. If so, they will have remains of the yolk sac like a deflated balloon sticking out from between their arms.
    Hatching must be a traumatic event in the life of the octopus embryo, just as being born is to humans. We go from being cushioned, warmed, protected, and nourished by our mothers inside their bodies to living by ourselves. We go