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I may be biased, and will delete if I'm wrong, but why are there so many more insects when compared to quad bugs?


marked as duplicate by AliceD, WYSIWYG Aug 26 '16 at 11:13

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    $\begingroup$ What is the question exactly? Afaik, there are no invertebrates with 2 pairs of legs only. Is the question why, while we see that 2 pairs of legs is a successful bodyplan in vertebrates? $\endgroup$ – Joce Aug 26 '16 at 8:15
  • $\begingroup$ By "bugs" you mean insects, right? All insects have six legs (some may be reduced). Arachnids have eight legs. You can see this answer for some explanation on why six legs may be favourable to many insects. In general, it is not easy to reason out "why" something happened. Many times evolutionary choices are just random. $\endgroup$ – WYSIWYG Aug 26 '16 at 11:13
  • $\begingroup$ @Joce I wanted to know why six legged invertebrates are more successful than their four legged counterparts $\endgroup$ – Adamawesome4 Aug 26 '16 at 16:27
  • $\begingroup$ @WYSIWYG Insects have six legs, and I want to know why is four not evolutionarily better for them $\endgroup$ – Adamawesome4 Aug 26 '16 at 16:28
  • $\begingroup$ I don't see how this is a dupe $\endgroup$ – Adamawesome4 Nov 20 '16 at 17:47

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