Nature's Adaptations for Protection

It is noteworthy in considering the capacities of beings we regard as much inferior to ourselves that both insects and animals make use of phenomena of which only the recent detective instruments of science have made us aware. It is known for instance, that "the activities of bats are mainly controlled by sounds too high pitched for us to hear. " Nature permits little to go completely to waste in the interplay of life. Would she not be likely to equip some of her hard pressed children with organs to enable them to take advantage of the vast forces of the extra penetrating rays?

The X-rays and other recently discovered forms of radiant energy are new to us; but they are not new in nature. Radium has been delivering them since this planet emerged from chaos and it is still found "in minute quantity distributed over the whole surface of the earth in soils, water and atmosphere. "

If the bees are able to use light of this kind; if they have been aware of it for millions of years, it may have been a directly determining factor in their racial continuance. Types which by development of the compound eye had most completely mastered its use would have had their chances of survival enormously enhanced.

Mystery of the Compound Eye

There is as yet apparently no very satisfactory explanation of the purpose of. the compound eye of Crustacea and Insecta. It is an eye totally different from the eye of the animal world. The ommatidia, or separate tubes, range from a few hundred to upwards of 30, 000 on each side. Those of the honey bees range from 4, 000 to 13, 000. A good description of these eyes is given by R. E. Snodgrass in a pamphlet for the Smithsonian Institution.

Even if we admit that nature appears often to go far out of her way to equip animals with complicated organs when simple ones would seem to meet all requirements, can we question that such a profoundly intricate structure as the compound eye must have been developed in response to some extraordinary need which the simpler eye could not meet?

The efficiency of any organ of primary importance is attested by the survival of the animals in which it is found. On this assumption, the compound eye has well proved its worth. Perhaps, however, it is now an inconvenience to some of its possessors, owing to change of habits, for types are known in which it is believed to be deteriorating, with the ommatidia decreasing in number.

In the Early Dawn of Life

The insect form, shared by crustaceans, is found among the earliest fossils. It would, in that remote past, have inhabited a planet much different from our present earth; a world in which vast clouds of steam rendered the air dark for weeks, or even years, much as the planet Venus is now thought to be enmeshed but in which the super rays probably were more active than they now are. A visual organ enabling its possessors to take advantage of the cosmic rays or the emanations of radium or other strongly penetrating energy would have been of supreme service to them. It is quite evident, at any rate, that in such an epoch an eye would have had to be evolved capable of functioning well in a common absence of clear sunlight and that the compound eye might be the response to this necessity.

Auguste Forel and Sir John Lubbock both made painstaking experiments with ants (which also possess compound eyes), to determine their reactions to ultra violet light. The ants' eyes were varnished; but it Dr. Swann's theory is true, the varnish used probably would not exclude the cosmic rays. These experiments were inconclusive.

Science is now offering us new paths of approach to many puzzling problems. We may be near a solution of the mystery of the honey comb, and in pursuit of such a solution I want to make some guesses-suggestions for students who have leisure interest and ingenuity to investigate them.

My Four Guesses

(First guess): The honey bee's compound eyes are formed for the purpose of taking advantage of strongly penetrating light rays on the ultra violet side of the spectrum. Thus the eyes are broken up into numerous tubes, or ommatidia, to lessen the impact of these strong rays on the visual centers. If the light to be utilized were weak, wouldn't an eye of opposite form, (the octopus type eye) have had to be evolved? It may be within the range of possibility that closer study of the compound eye will bring us new knowledge of the extra penetrating rays. Through millions of years this strange eye structure has been growing in efficiency, responding to the bee's need of a secure place for storing honey and rearing the young--a dry, warm, large cavity, necessarily dark so far as sunlight was concerned, but not impenetrable to rays now well known to exist.

(Second guess): The compound eyes have power to ab sorb sunlight or some other form of radiant energy, and later give it out slowly, as a battery absorbs power, which then becomes latent till needed. There is a whole world of mystery concerning the processes by which certain organisms are able to produce light, and E. N. Harvey, as a result of recent investigations comments: "An interesting question in the physical production of light is why bioluminescent radiation (and to a great extent phosphorescence and fluorescence) should be of short wave lengths''--that is, of wave lengths on the ultra violet side of the spectrum.

"The physical characteristics and the chemical processes underlying bioluminescence are practically an unexplored subject. "* Experiments on fireflies have shown that "light results from oxidation.....produced by the meta bolism of the light organs. " These experiments have resulted in the commercial production of a lamp that delivers light in a number of colors at "much less than half the radiant heat, as well as more light per watt than is obtained from incandescent lamps. "