Even if it could rear up and balance like that, the energy expenditure vs calorific gain seems like a losing proposition. You're talking about raising the center of gravity of it's 40-ton body mass by 10-20 feet just to grab a very small mouthful of low calorific leaves.
I'd guess the reason the sauropods had an extra long neck was rather so they could AVOID moving as much as possible - stand in one place and just swivel neck around to graze a large area.
That’s an ongoing debate within paleontology that often takes place on a species by species basis. The argument goes that since diplodocids (which this species is not) had heavy muscular tails, their center of gravity was near their hips, making it easy to rear up since they were effectively already a balanced seesaw and could use the tail as a third point of contact to balance. Other species in Mamenchisaurus share similar pelvic and tail features and M. youngi was show to have a stiff neck that couldn’t lift very easily, so it’s inferred that these may have reared as well. There are center of mass and skeletal models and stuff to determine whether rearing is possible but one hasn’t been made for this species specifically.
Sidenote: you underestimate the cardiovascular cost of pumping blood up a 5-15 meter neck. It’s not at all clear that a rearing strategy is more expensive energy wise.
Mostly I think this pose is a matter of logistics. They probably just had more vertical space than horizontal to work with for this exhibit.
I've got to wonder how realistic this pose is.
Even if it could rear up and balance like that, the energy expenditure vs calorific gain seems like a losing proposition. You're talking about raising the center of gravity of it's 40-ton body mass by 10-20 feet just to grab a very small mouthful of low calorific leaves.
I'd guess the reason the sauropods had an extra long neck was rather so they could AVOID moving as much as possible - stand in one place and just swivel neck around to graze a large area.
That’s an ongoing debate within paleontology that often takes place on a species by species basis. The argument goes that since diplodocids (which this species is not) had heavy muscular tails, their center of gravity was near their hips, making it easy to rear up since they were effectively already a balanced seesaw and could use the tail as a third point of contact to balance. Other species in Mamenchisaurus share similar pelvic and tail features and M. youngi was show to have a stiff neck that couldn’t lift very easily, so it’s inferred that these may have reared as well. There are center of mass and skeletal models and stuff to determine whether rearing is possible but one hasn’t been made for this species specifically.
Sidenote: you underestimate the cardiovascular cost of pumping blood up a 5-15 meter neck. It’s not at all clear that a rearing strategy is more expensive energy wise.
Mostly I think this pose is a matter of logistics. They probably just had more vertical space than horizontal to work with for this exhibit.
If they could eat from higher branches than others, they could avoid competition for resources.
if the head falls of, they'll have to take everything apart just to put the head back on
How can an animal even have a neck that long? Was it clear from the fossils that it is this long because I am skeptical.
No, there's no way to tell—the paleontologists probably just took a bunch of bones from the site and threw them together in a way that looked cool. /s
Now that is an idea for a The Far Side cartoon
He's got some neck!
this dinosaur has a soar throat