From Charles Douglas Wehner:

Re: Tiny “T. rex” found (Sept. 17): In humans, and most higher animals, the young are double-jointed.

During childhood, the young experiment with different body-postures. For example, western children sit on chairs whilst oriental children sit on the ground if it is warm. To keep the legs from getting in the way, oriental children knot their legs together - the “Lotus Position”.

At puberty, the sex hormones trigger the “closure of the epiphyses”. That is to say, instead of having a “ball-and socket-joint” that has one ball and two sockets, the adult has one ball and one socket. The other socket has cemented itself to the bone ball, and the gap between socket and ball has closed. The band of bone created is known as the “epiphysis” (Greek - “excrescent growth”).

Growth of the entire body now stops. The “set” of the joints, such as the knee-joint, has been optimised for the final, adult body-size. This is on the basis of habitual body-posture. The adult westerner finds the “Lotus Position” uncomfortable. The Oriental adult (from a warm part of the Orient) has no problem with this.

If at the time of Tyrannosaurus Rex, this optimisation system had not yet evolved, there would be NO NEED for a saurier to stop growing at puberty.

We have no living Tyrannosaurs. We do not know the growth-behaviour of the saurians. An examination of the epiphyses of the specimen would be needed in order to confirm that the “tiny Tyrannosaurus” had really stopped growing.