# Dicephalic (2-headed) turtles and snakes

**URL:** https://boards.straightdope.com/t/dicephalic-2-headed-turtles-and-snakes/656262
**Category:** Factual Questions
**Created:** [April 20, 2013, 9:36pm UTC](https://boards.straightdope.com/t/dicephalic-2-headed-turtles-and-snakes/656262 "2013-04-20T21:36:18Z")
**Posts on this page:** 5
**Page:** 1

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### Author: ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)
#### Post date: [April 20, 2013, 9:36pm UTC](https://boards.straightdope.com/t/dicephalic-2-headed-turtles-and-snakes/656262/1 "2013-04-20T21:36:18Z")

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According to [this Wiki article](http://en.wikipedia.org/wiki/Polycephaly), “The most commonly observed two-headed animals are turtles and snakes.” What is it about these reptiles that increases the probability of dicephalism, compared to other animals?

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### Author: ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)
#### Post date: [April 22, 2013, 2:20am UTC](https://boards.straightdope.com/t/dicephalic-2-headed-turtles-and-snakes/656262/2 "2013-04-22T02:20:29Z")

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bump

Someone’s gotta know about this.

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### Author: ![rhysf](https://avatars.discourse-cdn.com/v4/letter/r/f14d63/32.png) [@rhysf](https://boards.straightdope.com/u/rhysf)
#### Post date: [April 22, 2013, 2:52am UTC](https://boards.straightdope.com/t/dicephalic-2-headed-turtles-and-snakes/656262/3 "2013-04-22T02:52:36Z")

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I’m not sure the claim is true. The wikipedia article cites a Pravda article that doesn’t provide any references. Pravda mentions a researcher, Andrew Khund, who doesn’t show up through Google or PubMed. Nor can I find any other evidence to back it up.

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### Author: ![xnylder](https://avatars.discourse-cdn.com/v4/letter/x/bbce88/32.png) [@xnylder](https://boards.straightdope.com/u/xnylder)
#### Post date: [April 22, 2013, 5:14pm UTC](https://boards.straightdope.com/t/dicephalic-2-headed-turtles-and-snakes/656262/4 "2013-04-22T17:14:18Z")

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WAG about snakes: Because they are resilient animals with incredibly efficient metabolisms? It’s easier to survive having two heads when you only have to manage eating once every few weeks or months. But then I’m interpreting “commonly observed” to mean"surviving long enough to be observed," not necessarily “proportionally more being born”.

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### Author: ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)
#### Post date: [April 22, 2013, 5:39pm UTC](https://boards.straightdope.com/t/dicephalic-2-headed-turtles-and-snakes/656262/5 "2013-04-22T17:39:53Z")

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I’m not sure this is actually true. A web search shows lots of photos of two-headed snakes and turtles of various species, but quite a few lizards as well.

There are only a few of salamanders, and I didn’t see any photos that looked to be of authentic two-headed crocodilians or frogs.

Before speculating on causes in any differences, however, I’d want to see more evidence that the differences actually exist. As **rhysf** says, there doesn’t seem to be any actual research on this cited.
