Intelligence?

[boosh96]

I'm just curious-are there any studies or evidence out there that suggests chameleons are smarter than other reptiles? What I kinda figure is that their brains might have to be a bit more complex than at least some other lizards in order to process seeing two images at once, as well as switching to binocular vision and perhaps figuring out how far they need to extend their tongue in order to catch a prey item, as well as controlling their chromatophores and associating certain colors with certain feelings and moods. So how do you think chams stack up against other reptiles?

 

[Psychobunny]

I don't think more, or less 'intelligent' would be the right term.
Evolution has selected for them the specialized tools they need to survive and
multiply in their environment.
How their brains are able to co-ordinate that highly specialized visual acuity is still not understood.
Remember to, that chams do not have a well developed sense of smell, and have no outer, or middle ear (though they do have an inner ear).

So, while some reptiles may excel at one sensory input (like snakes tasting the scent of prey), other's have developed other survival skills.

 

[ridgebax1]

Apparently there are others who think they are smarter than we give them credit for. Interesting article:
http://jonlieffmd.com/blog/lizards-arent-supposed-to-be-this-smart

 

[Solid Snake]

I believe that its believed that when their eyes arent focusing on one thing at the same time, they are only seeing through one, or the other. Not two separate images, all the time.

I believe that they are of at least moderate intelligence, about the same as a dog. As far as understanding what is going on around them and such anyhow.

Youre not going to teach a chameleon to get you a beer, but that doesnt mean its not intelligent. It just means that the chameleon has absolutely no interest in pleasing you.

They do learn to recognize different people, and situations.

 

[kinyonga]

Vision...
Http://en.wikipedia.org/wiki/Chameleon_vision

 

[junglefries]

iq

Nova had a series on pbs a couple months ago. It showed monitor lizards who could count to six (as far as study had progressed) & identify between black and white items. I love my chams but that may be a stretch.

 

[Carlton]

Nova had a series on pbs a couple months ago. It showed monitor lizards who could count to six (as far as study had progressed) & identify between black and white items. I love my chams but that may be a stretch.

Monitors would almost definitely be the brains of the herp world IMHO. They need to be very adaptable and quick opportunists. I often think that in species that have developed unique specialized traits to increase their ability to survive (and I'm thinking of chammy things like their vision, skin change, unique body forms), some of these traits sort of replace their need for or dependence on higher intelligence. I don't think I'd describe any of my chams as highly intelligent compared to a monitor.

Specialized traits like binocular vision or color changing doesn't necessarily take more "intelligence" to manage, it just requires a brain that is organized differently. These traits are pretty involuntary responses, not rational reasoning (which is what most people would use to measure intelligence). The cham probably isn't deciding "am I really pissed at this intruder or should I fake it"? before turning color. They see an intruder, the stress hormones go up, chromatophores fire, and voila....color change!

Birds are a good example of taxa that sort of gave up reasonable voluntary thinking (and the brain space it takes) to adapt to better flight. Not only did they end up with lighter smaller skulls, but also gave more of the brain over to support finer vision, depth perception, body balance, etc. More of their behavior is based on instinctive type thought which takes less brain power and space. It always amuses me to think about owls. Humans often use an owl as a symbol of wisdom. Owls are one of the less intelligent birds...they gave it up in exchange for those wonderful eyes and ears.

Another thing humans tend to do is assume that species that are more socially sophisticated are more intelligent. So, species that react to the world a little more as a human might get this label of being smarter. Maybe it takes a more developed brain to gain the social graces. Maybe the brain developed a bit first, they became more socially complex, which resulted in more brain development etc etc etc. Chicken or the egg?

Well, what do I know anyway? I'm still trying to figure out how to keep my siblings from going for each other's throats while clearing out my Dad's house!

 

[fluxlizard]

I used to have an iguana who was amazing. Completely pet-quality, he was potty trained and would travel across the house, upstairs and into the bathroom where we kept his poopy tub and scratch to be put in. He would also scratch to be let outside, and we would let him out onto the back patio, he would go do his business, and sit in the sun a while and come back in the cracked open door when he was done. He sat in the back of our car (hatchback) in the window and on road trips we could open the door and he would go out and do his business in the grass and return. He knew individuals for sure- followed "snack givers" around the house and ignored others. He had to be taught with a lot of patience and time not to snack on the house plants (he snuck for a while after he learned not to do it in front of me but eventually I got him to stop that as well) and not to climb on the couch.

I used to think he was amazing and unique (and I still do) but nowadays you can see similar iguanas on youtube, as well as tegus and monitor lizards that show pretty intelligent behavior.

All that said, I really have a hard time believing some of the social behavior of the hatchlings in the article linked to in this thread- "group leaders" encouraging their group to enter the water and swim, for example. When terms like "encouraging" are used, I've got to wonder if someone isn't stretching things a bit. I also noticed "compete" was used and the fact that "compete" means fight with each other like animals rather than a spelling bee competition was sort of glossed over, making the "compete" behavior sound more intelligent than something male cockroaches do. But who knows? I was kind of amazed after the necropsy on the pet iguana that I described how much he could do with such a tiny little brain that he had...

Also not sure where chameleons rank in "intelligence". It seems to me that the larger lizards grow, the more "intelligent" their behavior appears. I really can't say I've seen anything close to iguana intelligence out of a chameleon. Although if you are looking for an intelligent chameleon- try a big one like oustalets or melleri. I'd say either of those seems fairly intelligent to me sometimes.

But then again- it sort of begs the question of what intelligence is and how can it be measured. Chameleons have a different strategy for survival that requires a certain level of shyness or at least relatively modest levels of physical activity. Their survival depends on being able to avoid notice- by predators and prey and competitors. A little different than a larger lizard who depends on speed and strength and swimming and jumping and foraging and digging for survival. But if all that extra activity is unnecessary for survival, isn't it more intelligent to have modest levels of physical activity?

It's like the douglas adams thing about the dolphins in the hitchhikers guide to the galaxy. People thought they were the most intelligent species because they built cities and computers and worked hard to do amazing things technologically, while all dolphins did was swim around catching fish. Dolphins thought they were the most intelligent for exactly the same reasons.

I've been meaning to do another lizard intelligence article on my blog sometime. Some guy at a university actually had as his job description jumping into big outdoor terraria with lizards and scaring them 3 times a day to see how intelligent they were based on how quickly they could learn which of 3 hiding places was the "safe" one that would not be disturbed by the guy after he scared the lizard. I seriously had no idea someone would be doing that as part of their living someday back when I was a student or I might have taken a different path in life. LOL

I do have a couple of intelligence articles on my blog with links to videos and research (by others- one interesting in particular with anole lizards at UVA problem solving) if anyone is interested- can click the link and find them. I'm terrible about writing so there aren't too many articles to sort through to find them.

 

[dom1959]

thanks to those that are contributing,
i love reading these type of posts