It is always good to see questions long thought answered come under
review with modern methods and produce much better answers that are
also clearly much more convincing.
It would be worthwhile to apply this also to sea life to discover if
any differences exist. It would also be good to apply it to Moas and chickens.
In the meantime, we are now going to be able to discuss the real
weights of the long extinct with serious confidence.
Dinosaurs lighter
than previously thought
by Staff Writers
Manchester UK (SPX) Jun 12, 2012
Scientists have
developed a new technique to accurately measure the weight and size
of dinosaurs and discovered they are not as heavy as previously
thought. University of Manchester biologists used lasers to measure
the minimum amount of skin required to wrap around the skeletons of
modern-day mammals, including reindeer, polar bears, giraffes and
elephants.
They discovered that
the animals had almost exactly 21% more body mass than the minimum
skeletal 'skin and bone' wrap volume, and applied this to a giant
Brachiosaur skeleton in Berlin's Museum fur Naturkunde.
Previous estimates of
this Brachiosaur's weight have varied, with estimates as high as 80
tonnes, but the Manchester team's calculations - published in the
journal Biology Letters - reduced that figure to just 23 tonnes. The
team says the new technique will apply to all dinosaur weight
measurements.
Lead author Dr Bill
Sellers said: "One of the most important things palaeobiologists
need to know about fossilised animals is how much they weighed. This
is surprisingly difficult, so we have been testing a new approach. We
laser scanned various large mammal skeletons, including polar bear,
giraffe and elephant, and calculated the minimum wrapping volume of
the main skeletal sections.
"We showed that
the actual volume is reliably 21% more than this value, so we then
laser scanned the Berlin Brachiosaur, Giraffatitan brancai,
calculating the skin and bone wrapping volume and added 21%. We found
that the giant herbivore weighed 23 tonnes, supporting the view that
these animals were much lighter than traditionally thought.
Dr Sellers, based in
Manchester's Faculty of Life Sciences, explained that body mass was a
critical parameter used to constrain biomechanical and physiological
traits of organisms.
He said: "Volumetric
methods are becoming more common as techniques for estimating the
body masses of fossil vertebrates but they are often accused of
excessive subjective input when estimating the thickness of missing
soft tissue.
"Here, we
demonstrate an alternative approach where a minimum convex hull is
derived mathematically from the point cloud generated by
laser-scanning mounted skeletons. This has the advantage of requiring
minimal user intervention and is therefore more objective and far
quicker.
"We tested this
method on 14 large-bodied mammalian skeletons and demonstrated that
it consistently underestimated body mass by 21%. We suggest that this
is a robust method of estimating body mass where a mounted skeletal
reconstruction is available and demonstrate its usage to predict the
body mass of one of the largest, relatively complete sauropod
dinosaurs, Giraffatitan brancai, as 23,200 kg.
"The value we got
for Giraffatitan is at the low range of previous estimates; although
it is still huge, some of the enormous estimates of the past - 80
tonnes in 1962 - are exaggerated. Our method provides a much more
accurate measure and shows dinosaurs, while still huge, are not as
big as previously thought."
University of Manchester
Explore The Early Earth at TerraDaily.com
I think the earth was smaller back in the dinosaur days. The gravity was less and movement of the massive beasts and birds were done with ease.
ReplyDeleteNeal Adams explains this theory so very well, and it makes so much sense along with the 'electric Universe' which I think is correct.