It is stated on this website that the density of a Grizzly bear bone is ten times our own. And since I am not into biology at all, I am confused as I don't understand the meaning of bone density here.
I know what the "bone mineral density" term means, and I know it is measured in $g/cm^2$, but there is also the "physical" density term which is the mass by volume and it's measured in $g/cm^3$.
Now, what does it mean when we say that an animal has a bone that is 10 times more dense than ours ? Does it mean that the bone weighs 10 times more for the same size (or volume) ? Or does it mean that it has 10 times the amount of minerals and so it is somehow stronger ?