Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Are humans the only species that has the troublesome prostate-urethra relation?

  1. Aug 18, 2007 #1
    just wondering. and if the answer is yes, any ideas as to how this came to be, in terms of evolution?
  2. jcsd
  3. Aug 18, 2007 #2
    I believe the answer is yes.

    Animals that are meat eaters, don't have seminal vesicles{example Lion}.Animals that have both prostates and seminal vesicles are herbivores{example Apes}.
    I have never heard of Apes haveing this type of cancer. There is some talk about our diet playing large roll in prostate cancer.
  4. Aug 19, 2007 #3


    User Avatar
    Staff Emeritus
    Science Advisor

    Is one referring to Benign Prostatic Hyperplasia or Prostate enlargement.


    Likely diet and life-style (e.g. sedentary vs active) have an effect, but I don't know of any study that has looked into that.

  5. Aug 20, 2007 #4
    Yea, I meant it in that sense, not cancer. Are humans the only animal that has the urethra passing right through where the prostate is? Or is this the same for all animals that have prostates and urethras?


    cool, I didn't know that, I figured all animals did.
  6. Aug 20, 2007 #5


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    What?! Sorry, but that's untrue. Diet has nothing to do with presence or absence of seminal vesicles. Carnivores don't have seminal vesicles (cats and dogs) but neither do marsupials, many of which are herbivores (i.e., Koala). Humans are not herbivores, but omnivores. But, none of that has to do with having a prostate.

    ALL mammals have a prostate gland. In humans, the prostate gland surrounds the urethra, while in other species it varies in shape, size and position, so enlargement of the prostate is less likely to constrict the urethra and interfere with urination, which is one of the early signs of an enlarged prostate in men.

    While a bad diet may be a risk factor for prostate cancer, this alone is insufficient to explain the incidence in humans.

    I don't think anyone has really even studied whether other species get prostate cancer. In the wild, if it were to occur early, it would be just another way an animal dies. For the most part, it's a disease of aging, which means one of the reasons we see it so commonly in aging men is that we've done such a good job at extending their lifespan by avoiding other earlier causes of death. For this reason, there is also no evolutionary pressure on this at all, because it occurs most frequently in men who are long past their reproductive years. In most animals, something else will get them long before they experience those sorts of diseases of aging.
  7. Aug 20, 2007 #6
    thanks again :smile:
  8. Aug 20, 2007 #7
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook