# Human foetuses have gills!?!? **URL:** \ **Category:** Factual Questions\ **Created:** [March 14, 2003, 1:52pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322 "2003-03-14T13:52:34Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![Scarf-Ace](https://avatars.discourse-cdn.com/v4/letter/s/bc79bd/32.png) [@Scarf-Ace](https://boards.straightdope.com/u/Scarf-Ace)\ **Post date:** [March 14, 2003, 1:52pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/1 "2003-03-14T13:52:34Z")
I read somewhere that human foetuses have the “vestigal remains” of gills at a certain stage in their development. Is this true? ---
**Author:** ![elfje](https://avatars.discourse-cdn.com/v4/letter/e/e19b73/32.png) [@elfje](https://boards.straightdope.com/u/elfje)\ **Post date:** [March 14, 2003, 2:11pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/2 "2003-03-14T14:11:14Z")
you can read all about it here: [http://www.rae.org/gillslit.html](http://www.rae.org/gillslit.html) [http://ourworld.compuserve.com/homepages/rossuk/recapitu.htm](http://ourworld.compuserve.com/homepages/rossuk/recapitu.htm) but, no, apparantly it’s not:) ---
**Author:** ![Jinx](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jinx](https://boards.straightdope.com/u/Jinx)\ **Post date:** [March 14, 2003, 3:38pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/3 "2003-03-14T15:38:37Z")
Bio majors, what’s that expression? Ontogeny recapitulates philogeny? Oh, I probably slaughtered that one… - Jinx :rolleyes: ---
**Author:** ![artemis](https://avatars.discourse-cdn.com/v4/letter/a/91b2a8/32.png) [@artemis](https://boards.straightdope.com/u/artemis)\ **Post date:** [March 14, 2003, 3:47pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/4 "2003-03-14T15:47:31Z")
> [@](#): > > \*Originally posted by Meta-Gumble \* > \*\*I read somewhere that human foetuses have the “vestigal remains” of gills at a certain stage in their development. Is this true? \*\* No. Human embryos have branchial clefts. So do fish embryos. In fish, the branchial clefts develop into gill structures as the embryo matures. In human embryos, the branchial clefts give rise to parts of the jaw and ears as the embryo matures. So human embryos never have gills, or vestigal gills. They merely have a structure that (in other vertebrate lineages) can differentiate into a gill slit. Evolution often works that way, adapting pre-existing structures (branchial clefts) to serve new functions (gill slits in fish, which are modified to jaw structures in amphibians and reptiles, parts of which later give rise to the bones of the inner ear in mammals). ---
**Author:** ![Podkayne](https://avatars.discourse-cdn.com/v4/letter/p/edb3f5/32.png) [@Podkayne](https://boards.straightdope.com/u/Podkayne)\ **Post date:** [March 14, 2003, 4:03pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/5 "2003-03-14T16:03:59Z")
The whole “ontogyny recapitulates phylogeny” princple has fallen into disrepute. It used to be trumpeted as a common-sense suport for evolution, but many examples of this principle turned out to be based on superficial resemblances and misconceptions. That’s not to say that one cannot learn about evolution by studying embryos, but the real picture is quite a bit complicated than human embryos having gills and tails. In an unfortunate display of Creationist-type behaviour, some Evolutionists (and by capitalizing that term I mean to indicate anti-Young-Earth-Creationists, as distinguished from, say, scientists who study evolution) have continued to trot out this canard. It’s an appealing notion, to be sure, but one that should probably be discarded in favor of stronger scientific arguments. ---
**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:** [March 14, 2003, 6:35pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/6 "2003-03-14T18:35:53Z")
> [@](#): > > \*Originally posted by Podkayne \* > \*\*The whole “ontogyny recapitulates phylogeny” princple has fallen into disrepute. \*\* In his _Ontogeny and Phylogeny_, Stephen Jay Gould pointed out that it is more accurate to say “ontogeny recapitulates ontogeny.” That is, embryos/fetuses do not pass through stages resembling the _adult_ forms of ancestral species, but may pass through stages similar to those of embryonic/fetal stages of ancestral species. The early stages of development are highly conservative; evolutionary modifications are more likely to appear at later stages of development than later ones. Embryonic humans at very early stages resemble embryonic fish (both having branchial clefts); they never resemble adult fish (having true gills). ---
**Author:** ![slipster](https://avatars.discourse-cdn.com/v4/letter/s/df705f/32.png) [@slipster](https://boards.straightdope.com/u/slipster)\ **Post date:** [March 14, 2003, 9:28pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/7 "2003-03-14T21:28:55Z")
This question was discussed at some length on this message board earlier this year. To recapitulate that discussion, and some of the material posted above: Human embryos do not have functioning gills. They have a series of slits–four on each side–which correspond to gill openings in some other species. The openings or pockets behind these slits develop into various structures. Two of them develop into the tonsils. Occasionally a slit fails to close entirely. It is not uncommon for people to have a very deep pin hole which corresponds to the end of one of these slits. This trait ran in the family of an old girlfriend of mine; her brother and his son both had marks of this kind on their neck. ---
**Author:** ![porcupine](https://avatars.discourse-cdn.com/v4/letter/p/ac91a4/32.png) [@porcupine](https://boards.straightdope.com/u/porcupine)\ **Post date:** [March 14, 2003, 9:33pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/8 "2003-03-14T21:33:05Z")
[Here](http://boards.straightdope.com/sdmb/showthread.php?threadid=158607) is an earlier thread on the topic. ---
**Author:** ![Ephemera](https://avatars.discourse-cdn.com/v4/letter/e/8baadc/32.png) [@Ephemera](https://boards.straightdope.com/u/Ephemera)\ **Post date:** [March 15, 2003, 6:21am UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/9 "2003-03-15T06:21:12Z")
Okay, so we don’t ever have gills… just slits that look like them. What about vestigal tales? Do some have those or is that just a urban legend too? ---
**Author:** ![Ephemera](https://avatars.discourse-cdn.com/v4/letter/e/8baadc/32.png) [@Ephemera](https://boards.straightdope.com/u/Ephemera)\ **Post date:** [March 15, 2003, 6:22am UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/10 "2003-03-15T06:22:19Z")
Er, tails. ---
**Author:** ![Eclectic\_Skeptic](https://avatars.discourse-cdn.com/v4/letter/e/e19b73/32.png) [@Eclectic\_Skeptic](https://boards.straightdope.com/u/Eclectic_Skeptic)\ **Post date:** [March 15, 2003, 8:32am UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/11 "2003-03-15T08:32:16Z")
I was born with a vestigial gill slit. But then again, I was born in Louisiana. ---
**Author:** ![Ca3799](https://avatars.discourse-cdn.com/v4/letter/c/9f8e36/32.png) [@Ca3799](https://boards.straightdope.com/u/Ca3799)\ **Post date:** [March 15, 2003, 4:58pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/12 "2003-03-15T16:58:19Z")
“I was born with a vestigial gill slit. But then again, I was born in Louisiana.” Hey, I resemble that remark, but then I always suspected a frog in the gene pool. ---
**Author:** ![irishgirl](https://avatars.discourse-cdn.com/v4/letter/i/8edcca/32.png) [@irishgirl](https://boards.straightdope.com/u/irishgirl)\ **Post date:** [March 15, 2003, 6:51pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/13 "2003-03-15T18:51:27Z")
Eclectic Skeptic, to you mean a branchial fistula? the facial muscles, pharynx, larynx, thyroid, thymus, mandible, facial bones, inner ear bones, tonsils and nasal cavity develop from pharyngeal arches. ---
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [March 15, 2003, 9:14pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/14 "2003-03-15T21:14:15Z")
> [@](#): > > \*Originally posted by Aesiron \* > \*\*Okay, so we don’t ever have gills… just slits that look like them. What about vestigal tales? Do some have those or is that just a urban legend too? \*\* An old girlfriend of mine had an extended tailbone thingie about 1/2 to 3/4 inch long. It had peachfuzz on it. I thought it was cute. I don’t know what it was (is?) though. Peace, mangeorge ---
**Author:** ![JThunder](https://avatars.discourse-cdn.com/v4/letter/j/e95f7d/32.png) [@JThunder](https://boards.straightdope.com/u/JThunder)\ **Post date:** [March 15, 2003, 11:15pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/15 "2003-03-15T23:15:08Z")
Well, the human skeleton has a coccyx [sub](okay, kids, stop snickering)[/sub], but it serves as an anchor for various muscles. It only resembles a tail in the most superficial of ways. ---
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [March 16, 2003, 12:06am UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/16 "2003-03-16T00:06:22Z")
Nah. Her’s was fleshy. WTF, I’m starting to breathe heavy. Anyway- This fellow knows what I’m talking about; [monkey trial](http://www.gennet.org/facts/metro07.html) Wow. Same guy, on the OP; [sound’s fishy](http://www.gennet.org/facts/metro06.html) This site is _not_ unbiased. ---
**Author:** ![Scarf-Ace](https://avatars.discourse-cdn.com/v4/letter/s/bc79bd/32.png) [@Scarf-Ace](https://boards.straightdope.com/u/Scarf-Ace)\ **Post date:** [March 17, 2003, 2:45pm UTC](https://boards.straightdope.com/t/human-foetuses-have-gills/161322/17 "2003-03-17T14:45:58Z")
Wow, thanks Artemis that clears it up nicely.