The evolution theory . ges. But from what I knew of the ontogenyof Smerlnthus species I was able to predict that, among the of Splihix, there must be some with sub-dorsal lines. Thiswas confirmed later, for Poulton found in Sphinx convolvuli thatin the first stage there are no oblique stripes, but only the sub-dorsalstripe, while in Sphinx ligudri both kinds of marking were presentat the same time. From all these facts, which I have summarized as briefly aspossible, we see that the older phyletic characters are graduallycrowded by the newer into ever-younger stages in the ontogeny
The evolution theory . ges. But from what I knew of the ontogenyof Smerlnthus species I was able to predict that, among the of Splihix, there must be some with sub-dorsal lines. Thiswas confirmed later, for Poulton found in Sphinx convolvuli thatin the first stage there are no oblique stripes, but only the sub-dorsalstripe, while in Sphinx ligudri both kinds of marking were presentat the same time. From all these facts, which I have summarized as briefly aspossible, we see that the older phyletic characters are graduallycrowded by the newer into ever-younger stages in the ontogeny, untilultimately they disapjDear altogether. We have now to ask to whatthis phenomenon is due ; is it a simple crowding out of the old and lessadvantageous by the new and better characters as a result of naturalselection, or is there some other factor at work ? It is clear in regardto these forms of marking that they can have been developed at firstonly in the almost full-grown larva by natural selection, because they.
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Keywords: ., bookauthorthomsonj, bookcentury1900, bookdecade1900, bookyear1904
