A theory which seeks to explain by natural causes the occurrence of every kind of adaptation which is to be met with in organic nature, on the assumption that adaptations of every kind have primary reference to the preservation of species, and therefore, also, as a general rule, to the preservation of their constituent individuals. This theory was first proposed by Darwin and is based on the following principles: overproduction of organisms and the consequent struggle for existence; the variations of organisms, useful and harmful, and the preservation of the useful, and destruction of the harmful; overcrowding; accidental destruction; change of habits; and migration. This theory is also termed the survival of the fittest (Herbert Spencer). It has not been established by fact, and is not now advanced even as a hypothesis to explain the origin of species.
This dictionary contains not only definitions and explanations of every subject in Religion, Scripture, tradition, doctrine, morals, sacraments, rites, customs, devotions and symbolism, but also accounts of the Church in every continent, country, diocese; missions, notable Catholic centers, cities, and places with religious names; religious orders, church societies, sects and false religions. It has brief articles also on historical events and personages, on the Old Testament and New, and on popes, prelates, priests, men and women of distinction, showing what the Church has done for civilization and correcting many errors which have hitherto passed for history.Wikipedia
Read More