Kaiju's don't work- biological constraints on size, mass, respiration, digestion, etc.

[pascal2]

Biomechanics seem to constrain how big and heavy living things can get- you couldn't have Godzilla because he'd collapse under his own weight- his bones would crush themselves, and pierce his organs. And as a respirating organism his lungs couldn't provide enough oxygen to maintain his metabolism given the room given over to them in his chest cavity. Similarly he couldn't eat enough either, given surface area/volume relations.

Any thoughts?

[Vmedvil5]

Well, I think that big dinosaurs did exist in the past so maybe it is possible to have a godzilla type creature if you remember the (Tyrannosaurus - Wikipedia). Life finds a way... I would think that there is some limit though based on the strength of bone and tissues however I don't know what that may be exactly at what size they would fail, below are some tensile strengths of various tissues and bones.

"The bones in your body are made from material which has a tensile strength of 150MPa, a strain to failure of 2% and a fracture toughness of 4MPa(m)^½."

"The tensile strength of the skeletal muscle along the fiber direction is 0.44 MPa at maximum load of 110 N and for direction 45 degrees inclined to the muscle fibers, the strength is 0.234 MPa at max load 43 N."

which steel has a tensile strength of

"The tensile strength for structural steel is 400 megapascals (MPa) and for carbon steel it is 841 MPa. Tensile strength values are different for different densities of steel. There are three types of tensile strength: Yield strength - The stress a material can withstand without permanent deformation."

which there are some pretty big buildings made of steel and bone is 37.5% as strong as structural steel so maybe it is possible to have a skyscraper sized dinosaur.

"The 828-metre (2,717 ft) tall Burj Khalifa in Dubai has been the tallest building since 2010."

Edited October 14, 2022 by Vmedvil5