Put the doggie in the basket...

Hi guys,
Question about cannibalism.
It's said that the more cannibalistic axolotls have a different appearance around the face and jaws. I was wondering what these are exactly? How can you spot it? Are these axies also more prone to adult cannibalism or do they grow out of it?

Thanks.

I have not heard about more cannibalistic axies looking different in terms of head and jaw region. Where have you heard of this and what was being mentioned?

I can however mention that wildtype axolotls tend to be more aggressive than other colour variants. In addition, they tend to be particularly/preferentially more aggressive to axies of other colour variants than wildtype. On a side note, wildtypes appear to be more robust/resistant compared to other colour variants in terms of illnness susceptibility and recovery.

Very young juveniles can also be more aggressive compared to their older counterparts.

Very hungry/starving axies can also display a more aggressive behaviour and nip at other axies (desperate for food perhaps).

A huge disparity in terms of size between axies can also encourage cannibalism.

Most cannibalism is accidental, during feeding frenzies.

Best way to prevent cannibalism is to avoid overcrowding, avoid housing different sized axies and providng plenty of hiding places and adequate food.

"Cannibalism is a natural tendency, and studies have been carried out on the cannibalistic variants of salamander larvae. If left to cannibalise their siblings, they actually develop different morphology (shape and appearance). This is most noticeable in the shape of the head and the teeth."

http://www.axolotl.org/rearing.htm

It also gives some links but I was hoping someone could give me a summary I've done enough journal reading today. I guess it does say 'if left to cannibalise' - and how often would that happen in a breeding situation? Not much I guess.

Thanks for that info too! Muchly appreciated.

I don't know about axolotls having a different shape but I am pretty sure I read somewhere that cannibalistic tiger salamander larva have a different look.

I am pretty sure that article refers to the tiger salamander. I have not seen a different 'cannibalistic look' shaped head or jaw type in axies ever. All axies have very similar faces to me, or maybe i am just not good at picking subtle difference in axie features.

I would think terrestrial salamanders can possibly develop a different shaped head due to the food type or hunting behaviour but for neotenic, fully aquatic species, the conformational changes will be quite restricted as features like the gills in axies will still have to be retained. Skull and jaw changes will be slight at best.

222693 said:

Hi guys,
Question about cannibalism.
It's said that the more cannibalistic axolotls have a different appearance around the face and jaws. I was wondering what these are exactly? How can you spot it? Are these axies also more prone to adult cannibalism or do they grow out of it?

Thanks.

Click to expand...

Years ago, I found a scholarly article on the web discussing just that: Morphological differences of the jaw and tooth structure of Ambystoma mexicanum allowed to eat its siblings.

Sadly, I have been unable to find the article or even remember its exact title. (I have been searching for it for months now.)

In my personal experience, larval axolotls that are allowed to prey on their conspecifics seem to do better in the long run.
I have no idea if this is a direct result of the canabalism or just a result of a less crowded environment.

I do have to admit, the larger ones make dealing with runts much easier!

I think the best person to ask about details of the morphological differences will be John. I really haven't seen any literature about it. I suspect those axies may not be pure axies. They could have a large proportion of tiger salamander in them.

With scientific journal articles, its important to critically evaluate a quality as well. Just because its published, doesn't always mean its accurate or correct. Sometimes terminology can be mingled, experimental design (ie sample size/confounders) are not properly addressed, statistical analysis may not be ideal or powerful enough etc. I would tend to go with looking at a series of related papers and then synthesizing the information accordingly. I have seen books and articles use axolotls interchangeably with tiger salamanders or group them under the same name.

It is theoretically possible that over many years, 'normal' and not 'pathological' morphological changes can occur such as breeding for specific traits - such as different dog breeds skulls (even though all descend from wolves).

I hatched 15 eggs (leucistic) in February, & they grew at very different rates (several are mis-shapes gill-wise). A few weeks back I decided that the 2 tiniest ones were big enough not to be eaten by 'Big Bro', & moved them all to a 5', well planted tank. Some weeks later I saw 'Big Bro' accidentally grab a 'tiny', but quickly spit it out - no WAY would it fit - although BB was sizeably larger, not THAT much so, judging on the size slugs it could eat...........one Monday morning he was VERY fat & one 'tiny' was sadly gone.........BB is now called 'Spot' & lives with adult 'Sparkle'!!!

He also took 2 gills off tank newby 'Bonzo' - a wild-type, nearly his own size, which he visably disliked! Bonzo is much more relaxed now 'Spot' has moved, & shows no tendancies to eat the 2 tinies himself!

Live (or not) & learn..........

Heather & Sparkle