  The living organism is considered as an open system, whereas Prigogine's
approach to the thermodynamics of such systems is used. The approach allows one
to formulate the law of individual growth and development (ontogenesis) of the
living organism, whereas it has taken into account that the development and
functioning of the system are occurring under the special internal program. The
thermodynamic equation of growth is followed a method of estimation of the
specific entropy of organism. The theory is compared with experimental data,
whereas estimates of the specific entropy of some species were done; it shows a
reduction of specific entropy in the evolutionary row: yeast - insects -
reptiles - birds.
