Specimens of Tyrannosaurus and colleagues announced the recovery of soft tissue from the marrow cavity of a fossilized leg bone (a 1.15 m long femur), from a 68-million-year-old "Tyrannosaurus". The bone had been intentionally, though reluctantly, broken for shipping and then not preserved in the normal manner, specifically because Schweitzer was hoping to test it for soft tissue. Designated MOR 1125 (and known informally as B-rex), the dinosaur had been excavated from the Hell Creek Formation. Flexible, bifurcating blood vessels and fibrous but elastic bone matrix tissue were recognized. In addition, microstructures resembling blood cells were found inside the matrix and vessels. The
Spongy tissue Spongy tissue Spongy tissue is a type of tissue found both in plants and animals. In plants, it is part of the mesophyll, where it forms a layer next to the palisade cells in the leaf. The spongy mesophyll's function is to allow for the interchange of gases (CO2) that are needed for photosynthesis. The spongy mesophyll cells are less likely to go through photosynthesis than those in the palisade mesophyll. It is also the name of a disorder of fruit ripening which can reduce the value of a fruit yield, especially in mango. In the alphonso mango variety, this