. The wonder of life. Biology; Natural history; Zoology. THE WONDER OF LIFE 621 become like a gizzard, with thick and muscular walls. This is associated with a unique reduction of the front of the breast-bone, and a consequent lessening of the area for the attachment of the muscles of Fig. 98.—New Zealand Lizard, Sphenodon or Hatteria, an archaic reptilian type, sole survivor of the ancient race of Rhynchocephalia. (lY'om a specimen.) Conservation in Evolution.—We wish to expand the idea of the hving past into a general conception of the conservative tendency in evolution. There is, i
. The wonder of life. Biology; Natural history; Zoology. THE WONDER OF LIFE 621 become like a gizzard, with thick and muscular walls. This is associated with a unique reduction of the front of the breast-bone, and a consequent lessening of the area for the attachment of the muscles of Fig. 98.—New Zealand Lizard, Sphenodon or Hatteria, an archaic reptilian type, sole survivor of the ancient race of Rhynchocephalia. (lY'om a specimen.) Conservation in Evolution.—We wish to expand the idea of the hving past into a general conception of the conservative tendency in evolution. There is, it seems to us, a very Uteral sense in which we may think of the higher animals as heirs of all the ages. Particularly effective modes of vital behaviour, some of which made a fortune in their day, yet did not save their possessors from utter ruin, have been caught up by collateral relatives and handed on as a legacy from by-gone ages to the higher animals. Where, for instance, would a higher animal te—^what possibiUty of such a hfe would there be—without a persistence of that most primitive manifestation of hfe which we call amceboid movement—the ebb and flow of a protoplasmic tide—so famihar to students of biology in amoebae and white blood corpuscles ? How long would a higher animal survive without its body-guard of phago- cytes ? Nor could it have become what it is, had not its embryonic nerve-cells flowed out into nerve-fibres, just like exploring Amoebse!. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Thompson, John Arthur, Sir, 1861-1933. London, A. Melrose, Ltd
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Keywords: ., bookcentury1900, booksubjectnaturalhistory, booksubjectzoology
