Why the bristles in a bristlenose.

Hi;
Watching my male bristlenose Boris today, I came onto a thought that I cannot find the answer to.
Why does the male have the bristles ????
Now it can't be a taste organ for food such as catfish barbels because if it was, the females that have few or none would be at a great evolutionary disadvantage and they would develop the same through natural selection. Anyway they seem to be on the wrong spot, as they would then be on the bottom and not the top of the head.
The only thing I can think of is that males with more and bigger bristles attract the females. That somehow they find it "sexy" and the one with the the biggest thing gets the girls so to speak.
I would love to hear from some people who have breed them and if the size of the bristles effects the amount they tend to breed.
Or if evolution again throws a spanner in the works as the trend would be to bigger and more spread bristles. Also why do some females have any at all, if only small ?
Just something interesting to think about.
Marty

You have hit the nail on the head

The only thing I can think of is that males with more and bigger bristles attract the females. That somehow they find it "sexy" and the one with the the biggest thing gets the girls so to speak.

This is correct, Same as a lion's mane, the bigger brighter the mane, the better looking & better father apparently

There is a whole section in my book dedicated to this question

There are also several scientific papers written on the subject.

I could re-write it all but, well, i'm a poor uni student, help a brother out

I read that female bristlenoses find males more attractive if they already have fry in the cave. The bristles are meant to look like fry clustering round the male. Don't know how well tested that theory is but its sounds cool.

edit: Its on Wikipedia with a very badly scanned in scientific paper to support.

Ony wrote:

I read that female bristlenoses find males more attractive if they already have fry in the cave. The bristles are meant to look like fry clustering round the male. Don't know how well tested that theory is but its sounds cool.

edit: Its on Wikipedia with a very badly scanned in scientific paper to support.

Hi,
Very interesting theory. I also think it is a sexual signal. But I just wonder if the larger bristled males "get more" so to speak and hence there would be a tendency through evolution for larger and more elaborate bristles.
Also why do females get them if only small as nature does waste anything and growing bristles on a girl is a bit of a waste unless they are particulary "butch" I guess.
Hmmmmm !!!!!

I've also heard the whole "sexy" approach to this theory as well. But I did read somewhere (or heard, I'm not sure) that the bristles on the male can "sense" so to speak, the pheromones given from females. In this theory I would guess that this ability would tell the male if the females around or near his cave are ready to spawn or if they are simply getting in the way of his guarded space.

Either way, I have often wondered what the true reason was behind those bristles on both genders.

Silvashadow wrote:

I've also heard the whole "sexy" approach to this theory as well. But I did read somewhere (or heard, I'm not sure) that the bristles on the male can "sense" so to speak, the pheromones given from females. In this theory I would guess that this ability would tell the male if the females around or near his cave are ready to spawn or if they are simply getting in the way of his guarded space.

Either way, I have often wondered what the true reason was behind those bristles on both genders.

Your pheromones idea does sound interesting. But you are right it does not explain why females have them, even if not as pronounced as the males.
Marty

the sensing theory has long been out dated. Initially this theory was solid as people discovered that the bristles were covered in taste buds. However, there are two holes in this theory, first, as mentioned before it does not explain the sexual dimorphism and second it has been shown more recently that their entire body is covered in taste buds.

The fry mimicry theory is the current and as far as i can tell, correct theory. as to why the females sometimes get little ones. It is impossible to selectively breed for a trait like that without some form of sexual crossover. Think of it this way. If being really hairy as a bloke was decided by all women to be the most desirable thing then undoubtedly you would see over time an increase is the hairyness of men. As a by product though, you would notice a thickening and darkening of the hair on women too...and most likely an increase in the sale or razors.

Doug wrote:

the sensing theory has long been out dated. Initially this theory was solid as people discovered that the bristles were covered in taste buds. However, there are two holes in this theory, first, as mentioned before it does not explain the sexual dimorphism and second it has been shown more recently that their entire body is covered in taste buds.

The fry mimicry theory is the current and as far as i can tell, correct theory. as to why the females sometimes get little ones. It is impossible to selectively breed for a trait like that without some form of sexual crossover. Think of it this way. If being really hairy as a bloke was decided by all women to be the most desirable thing then undoubtedly you would see over time an increase is the hairyness of men. As a by product though, you would notice a thickening and darkening of the hair on women too...and most likely an increase in the sale or razors.

Very true, I agree.
But it goes to show how little we know and understand about the creatures we share our lives with. Totally amazing.
If only fish could talk.
Marty

marty14 wrote:

If only fish could talk.
Marty

If only indeed. The abundance of information we could get if they could even whisper would be phenomenal.
These pleco fish never cease to amaze me though, every detail written about them is interesting. Though I do wonder when the scientists are gonna slap down the fact on the bristles and say with definite confirmation what purpose those mesmerising strands are truly for.

Silvashadow wrote:

marty14 wrote:

If only fish could talk.
Marty

If only indeed. The abundance of information we could get if they could even whisper would be phenomenal.
These pleco fish never cease to amaze me though, every detail written about them is interesting. Though I do wonder when the scientists are gonna slap down the fact on the bristles and say with definite confirmation what purpose those mesmerising strands are truly for.

I wonder if anybody will decide to their PhD on the purpose of the bristles in bristlenose. Can't be any worse then some topics people use to do their phD. That would really be interesting.
Marty

No one will ever be able to say with 100% certainty what the bristles are for. First rule of science, you can never prove anything, you can only disprove things.

I would gladly do another PhD on it. The fact is that a PhD normally ends up costing about $100,000 and unfortunately i'm not in a position to cough that up, not yet anyway The other issue is that there is no management outcome from this topic. Sure it is interesting but what is the benefit to greater society? My PhD looked at population genetics and dispersal ability of aquatic macroinvertebrates in ephemeral systems. Interesting? some would say yes, others no, however, there is strong management outcomes and the results can be used in the management of ephemeral waterways across the planet.

Doug wrote:

No one will ever be able to say with 100% certainty what the bristles are for. First rule of science, you can never prove anything, you can only disprove things.

I would gladly do another PhD on it. The fact is that a PhD normally ends up costing about $100,000 and unfortunately i'm not in a position to cough that up, not yet anyway The other issue is that there is no management outcome from this topic. Sure it is interesting but what is the benefit to greater society? My PhD looked at population genetics and dispersal ability of aquatic macroinvertebrates in ephemeral systems. Interesting? some would say yes, others no, however, there is strong management outcomes and the results can be used in the management of ephemeral waterways across the planet.

Excellent point about never being able to proof anything. But one could try to disprove some of the theories going around.
Regarding the cost you could always get some government department to sponsor you. After all what really did we need a female surfboard for anyway ???? (Remember that)
Your PhD sounds interesting and you are right, there could be uses for it such as in fisheries. Sounds interesting.
I only got up to two different honours thesis that I completed but both where boringly useless by today's standard (I guess that is why I never got invited to do my PhD), but I digress.
Marty