Tarantulas Feeding through Evolution??

[Drachenjager]

Vipers have fangs that probably could break through a hard outer exoskeleton but after which it would not be able to make a meal of the insides of the insect. Arachnids can due to the different feeding style.

actually i am sure that the venom would liquify the inners of an insect but the sanke would swallow it hole. also Tarantulas dont suck the innards out of the feeders. In fact i seldom find any left overs in my T tanks , until i fed large roaches lol then i found some. but they do masticate the prey .

 

[kasai]

Guys guys! I think what Steph is trying to figure out here is if, despite the fact that they are capable of eating mice and rodents, if they are more specialized to hunt and capture inverts... which, according to most tests on venom is certainly true... but they are also very capable of killing and eating mice, small birds, and small reptiles- DEPENDING ON THE SPECIES AND SIZE.

So, yes, and no, to Steph's question. Yes, they are specialized, however because they can, have, and will certainly hunt, kill, and eat small vertibrates when the oppertunity arises (as tarantulas are indeed oppertunistic hunters).

But jeez, seems you guys are too (oppertunistic hunters), you certainly seem to jump on Steph! Is there any reason for this? :?

 

[zimbu]

Tarantulas have large fangs primarily to break through and penetrate an exoskeleton. They also have special enzymes that breakdown and digest the inside of an exoskeleton…. am I right? So by evolution they are primarily meant to eat insects with hard exoskeletons. Ok you guys go with it and tell me what you think.


Steph

If you look at more primitive Chelicerates, their mouthparts are generally clawlike, with the second last segment containing the fixed "thumb" and the last segment acting as the moveable "finger". Since Chelicerates cannot eat solid food (with the exception of the Opilionids), the mouthparts adapted for tearing and mashing are an effective, if not the most efficient, way of extracting edible liquid from food items.

If you look at a variety of major taxa within the Chelicerates, many of them have evoled secondary means of masticating their food to facilitate their liquid diet. For example, horseshoe crabs have a ventral "food groove" which is comprised of spiked coxa which grind their food as it nears their mouth, scorpions have venom to help break down their prey's tissues, and solifugids simply have massive chelicera to grind their prey to a pulp.

Arachnids on the other hand, have evolved so their once chelate (pincerlike) chelicera are now jackknife shaped, unsuitable for grasping and tearing prey. They do however have venom glands which are an extremely effective way of reducing their prey to liquid. So personally, I believe their piercing fangs are not an adaptation for eating arthropods so much as they are an effective venom delivery system. However, at the time this evolved they certainly had an exclusively arthropod based diet, because no other group of animals had yet moved onto land where arachnids evolved. Since arachnids first evolved on land, many other species have colonized the land as well (including vertebrates), and spiders are just as willing to hunt them.



Oh and actually Viper venom is quite similar to spider venom in that it helps break down the prey's tissues. It facilitates the digestive process up quite a bit in that group of snakes, which is one of the reasons that vipers can live in colder climates then many other snakes.

 

[rattler420]

i beleive any creature with fangs evolved with them mearly as a way to get thier venom into thier prey. thats why a T's fang so closely resembles a front fanged snakes, its the most efficient way of injecting venom.

 

[kasai]

If you look at more primitive Chelicerates, their mouthparts are generally clawlike, with the second last segment containing the fixed "thumb" and the last segment acting as the moveable "finger". Since Chelicerates cannot eat solid food (with the exception of the Opilionids), the mouthparts adapted for tearing and mashing are an effective, if not the most efficient, way of extracting edible liquid from food items.

If you look at a variety of major taxa within the Chelicerates, many of them have evoled secondary means of masticating their food to facilitate their liquid diet. For example, horseshoe crabs have a ventral "food groove" which is comprised of spiked coxa which grind their food as it nears their mouth, scorpions have venom to help break down their prey's tissues, and solifugids simply have massive chelicera to grind their prey to a pulp.

Arachnids on the other hand, have evolved so their once chelate (pincerlike) chelicera are now jackknife shaped, unsuitable for grasping and tearing prey. They do however have venom glands which are an extremely effective way of reducing their prey to liquid. So personally, I believe their piercing fangs are not an adaptation for eating arthropods so much as they are an effective venom delivery system. However, at the time this evolved they certainly had an exclusively arthropod based diet, because no other group of animals had yet moved onto land where arachnids evolved. Since arachnids first evolved on land, many other species have colonized the land as well (including vertebrates), and spiders are just as willing to hunt them.



Oh and actually Viper venom is quite similar to spider venom in that it helps break down the prey's tissues. It facilitates the digestive process up quite a bit in that group of snakes, which is one of the reasons that vipers can live in colder climates then many other snakes.

Beautiful answer, very informative! :clap:

 

[Drachenjager]

But jeez, seems you guys are too (oppertunistic hunters), you certainly seem to jump on Steph! Is there any reason for this? :?

i am sorry but i suppose i dont understand this statement. It seems i only saw one person do anythign that resembled "jumping on Steph" . and I dont think that was actually the intention, but i cold be wrong.
If you ask a question, and think you have the answer , you shoudl be prepaired for others to have a differant answer. Of course there is absoulty no reason to be rude about it.

 

[zimbu]

Beautiful answer, very informative! :clap:

heh, thanks, I just took a year long invertebrate zoology course as part of my Zoology major... I'm still kinda used to giving essay format answers in response to any question anybody asks of me.

 

[verry_sweet]

Yes Kasai that’s exactly what I was trying to get at but I didn’t feel attacked in any way….Thank you for the concern though

I was thinking more about this while doing dishes and tarantulas must have been so successful with surviving for this long because they are opportunistic. When insect’s numbers are down they can eat vertebrates and the other way around. I think I get it now

Animals that are specialized to one food source will suffer if there food supply drops massively eventually even leading to extinction.

 

[Drachenjager]

Yes Kasai that’s exactly what I was trying to get at but I didn’t feel attacked in any way….Thank you for the concern though

I was thinking more about this while doing dishes and tarantulas must have been so successful with surviving for this long because they are opportunistic. When insect’s numbers are down they can eat vertebrates and the other way around. I think I get it now

Animals that are specialized to one food source will suffer if there food supply drops massively eventually even leading to extinction.

yep and extinction sux,
and Stef is too sweet to attack

 

[verry_sweet]

yep and extinction sux,
and Stef is too sweet to attack

Yah it takes me a while before I can wrap my brain around some thoughts/ideas.


Sweet Haha ;P if you only knew the truth

 

[Quizzler]

Canines are for tearing meat into pieces, tarantulas do not eat like that

 

[AfterTheAsylum]

Tarantula venom has peptides that act against vertebrates. I guess that's all I need to say. It's too late for me to be talking.

Drachenjager, rock on.

 

[Brian S]

A tarantula is an opportunistic predator that will attack and kill anything it can over power for food. I wouldnt say that a T's fangs are NOT specialized to eat inverts only however inverts would certainly be the prey of choice not due to design of the fangs but more due to size. It takes a pretty good sized T to handle a mouse or even a lizard.