Math Is Fun Forum

You are not logged in.

#1 Re: Dark Discussions at Cafe Infinity » do fish have a personality » 2005-07-28 22:21:34

ganesh wrote:
thinkdesigns wrote:

i don't think fish have real process of their mind, it is proven that they don't feel pain.

It is wrong to assume fish don't feel pain. Any member of the animal kingdom that reacts to touch does feel pain (I think :))

If you hit an anaesthetized person, they will react to the "touch" - but do they really feel pain? I'm pretty sure the same thing would happen to any anaesthetized animal - but I've never heard anything about it.  Also headless chicken will react to stimulus such as touch but Im pretty sure they don't feel pain.

Have a look at Nociception.

An interesting experiment done regarding fish feeling pain has been covered by BBC News. In a nutshell they injected a group of fish with bee venom into their mouths. They proceeded to observe obvious signs of pain. This in its self is quite easily passed off as a reflex reaction.

They continued to observed the fish injected with bee venom doing peculiar things such as rubbing their mouths on gravel and the tank walls. This behavior is passed off again as a "reflex reaction". But when they went to feed the stung fish, they observed that the fish took 3 times longer to resume eating than the control group. Now, I don't see any other explanation but that fish feel pain...

MathIsFun wrote:

Good experimenting, too.

Thank you, but it's more for bragging rights (Watch, my trained gold fish) and also a pretty good conversational piece.

#2 Re: Dark Discussions at Cafe Infinity » do fish have a personality » 2005-07-27 22:31:12

I've had gold fish since I was about nine. I dont think I could count that times I have been told the story about gold fishes memories (from anywhere from 3 seconds to 3 minutes). On TotalyWild (and Australian TV show?)  they showed how they trained a fish (admittedly not a gold fish, but another small one) to do circles in the water on cue and then receive food as a reward.

A few months a go I decided to do get a plastic shower curtain ring (which floats well), and place it in the water. The fish just ignored it. Instead of just randomly placing food in the aquarium, I  decided to put the fish food inside the ring. Once the food was in the equation, the fish immediately reacted and swam underneath the ring to quickly grab as much food as they can. Once finished, I removed the ring from the water.

For a week, I kept placing the ring in the water, shortly before putting the food inside it. It was then that I started noticing that as soon as the ring was placed in the water, the fish would slowly swim to it, anticipating the food. Once finished, again I would remove the ring.

Now, I have been doing this (for a few months), and as soon as the ring hit touches the surface of the water the gold fish get excited and race over the ring  knowing that is where the food will be. So, aspects of fishes memories must last a lot longer than we would expect. I almost think that fact was made up by people to feel better about storing fish in tiny boring containers  but I dont think a fishes brain and memory is complex enough to allow it to get bored of an aquarium.

I did a quick search and found this site: … ing_a_fish which uses "Teaching By Reward Only" to train gold fish, and  with cues such as flashing a light, or tapping the bowl  they claim their gold fish were trained to do things such as:

  swimming under and through a ceramic bridge, or castle, or loop made from bent coat hanger wire.
  swimming in a circle in open water.
  swimming backwards.
  swimming to a finger target placed against the bowl.
  following a laser pointer spot on the pebble floor of the tank.

Also thinkdesigns, have you ever done casual fishing? I don't see how you could possibly think that fish don't have brains or feel pain. I have done a limited amount of fishing, and all I really catch is catfish - but when you pull the hook from their mouths, it's a pretty clear that they feel pain ('specially 'cause catfish sort of yelp and cry when you pull the hooks from their mouth). On the other hand, I don't think fish have personalities (or attitude).

One amazing thing when scuba diving is how the school of fish move  and react to stimulus  its really very interesting. (I swear the only reason this is so long is because I have a lot of work to do, and any form of procrastination will do (even if its no better than what I am procrastinating)).

#3 Re: Help Me ! » As easy as it seems? » 2005-07-25 09:32:11

Thanks a lot mathsy, I can see what you've done and understand it (but it would be another thing for me to be able to do it).

MathsIsFun, I'll try remember the:
ax² + bx + c = 0
x = (-b ± √(b² - 4ac) / 2a

Thanks a lot guys, it's much appreciated!

#4 Help Me ! » As easy as it seems? » 2005-07-24 23:14:09

Replies: 5

I came across this little problem:

A rectangular room is 3 meters longer than it is wide. If the area of the floor is 88 square meters, what is the length and width of the room?

The problem looked a little like a joke, but just for entertainment - I tried solving it. Half an hour later, I had absolutely no idea where to go. (Obviously after a couple of minutes, I couldn't help noticing the answer, but that's not what I am after).

Could anyone please tell me how to solve this "tricky" problem.

BTW, I've had the problem at "(width * 3) + ( width * width) = 88" but I could get no farther.

Thanks for putting my mind to rest.

Board footer

Powered by FluxBB