Abstract: In this research, we unify theory of evolution in biology with string theory in cosmology and propose a unified Darwinian string theory. In this theory, first a zero dimensional manifold decays into two types of closed strings, one generating cosmos and another producing biosystems. This event is called bio-big bang in a biocosmos . Cosmic closed strings decay into cosmic open strings. Some of these strings produce dimensions, universes and anti-universes. Some others create planets, stars, matters and anti-matters. Bio-closed strings decay into open bio-strings. These strings create biological matters like DNAs in universes, biological anti-matters like anti-DNAs in anti-universes and biological mixtures of matters and anti-matters within center of planets. Summing over charges of these three groups of biological matters is zero. These biological matters exchange states with each other and form a triangle of life. Each gene of a DNA acts like the receiver or sender of radio waves. To control exchanging waves between genes on planets, anti-genes in extra dimensions and genes or anti-genes within the center of planets, three types of neuronal circuits are emerged. A collection of these neurons produce neural network within the brain. When a creature is died or turn off , its DNA's states are transformed into center of planets or anti-universes. If DNA of a dead cell is located within an egg of a female, neurons of her brain take signals relating to dead cells from the center of planet, transform to the egg cell and reproduce creature or cells again. If some neurons are hurt and a part or all the brain is died, the best way is connecting a system of heart-brain to it's related heart. In these conditions, some waves are sending from biological system within the planet, taken by neurons of second system, transform to the heart of that patient, reprogram blood cells and produce new neurons within the initial brain. On the other hand, exchanging of waves between bio-system within the center of planets and DNAs on it depends on the location of creatures and thus, animals and humans have different shapes in each point of planet. In addition to these biological effects, biological system within the center of planet produce its magnetic field and temperature so. Because each gene is built from charged particles and by motion of them during orbiting of planet around star or in cosmos, a current is appeared. Each current produces a magnetic field around the planet and summing over all fields results in producing known magnetic field within the center of planet. Also, some metals within the planet play the role of mirror and induce some anti-genes. In addition, some anti-genes are induced from extra dimensions. These two groups of anti-genes produce negative currents and magnetic fields in opposite direction respect to the magnetic field of genes. Consequently, magnetic fields of genes and anti-genes cancel effect of each other and total magnetic field of planet shrinks to known values. On the other hand, temperature depends on the energy of current and this energy decreases from infinity at center to lower values on the boundary and thus temperature is huge at center. Also, this temperature is reduced by currents of anti-genes and achieve to known values on the planet. Thus, this theory is in agreement with both biology and cosmology in a biocosmos.