“Populations interact, some decline to extinction, and some expand. In an ice age the tundra advances on the forest, but in no sense is there a "struggle" between them. As the temperature gets colder, the forest species decline and the tundra species increase; that is all. There is neither effort nor fight. As we move toward the more complex animals, of course, both effort and fighting become more common, but even in the predator-prey relationship, there is catching and eating rather than fighting.”

Mutual Aid: A Factor of Evolution (1902)
Context: In the animal world we have seen that the vast majority of species live in societies, and that they find in association the best arms for the struggle for life: understood, of course, in its wide Darwinian sense — not as a struggle for the sheer means of existence, but as a struggle against all natural conditions unfavourable to the species. The animal species, in which individual struggle has been reduced to its narrowest limits, and the practice of mutual aid has attained the greatest development, are invariably the most numerous, the most prosperous, and the most open to further progress. The mutual protection which is obtained in this case, the possibility of attaining old age and of accumulating experience, the higher intellectual development, and the further growth of sociable habits, secure the maintenance of the species, its extension, and its further progressive evolution. The unsociable species, on the contrary, are doomed to decay.

Source: The Human Comedy : As Devised and Directed by Mankind Itself (1937), Ch. 2

Axelrod, Robert, and William Donald Hamilton. "The evolution of cooperation." Science 211.4489 (1981): 1390

Source: Star Maker (1937), Chapter XVI: Epilogue: Back to Earth (p. 188)

Lo que más interesante es en la naturaleza existen dos especies, unicamente dos especies que son expansionistas: el hombre y los insectos. Las demás especies son territoriales. El insecto es devorador, expansionista, hasta que se siegue expandiendo y no le importa. Y el hombre es así... las dos especies que van a acabar peleándose por el mundo van a ser insectos y hombres.
Interview with Guillermo del Toro. http://www.filmoteca.com/sec4/guidtoro.htm

Source: The Faraway Nearby

All the King's Men' A search for the colonial ideas of some advisers and "accomplices" of Leopold II (1853-1892). (Hannes Vanhauwaert), Emile Banning (1836-1898): The Don Quichotte of the ‘liberal civilization’ in Congo, A romantic associate of Leopold II. http://www.ethesis.net/leopold_II/leopold_II.htm#_ftn194 E.B. La Belgique doit être agrandie. Hoei, 1882, 16-17.

“ Gold Is Not the Real Measure of a Nation http://www.guardian.co.uk/commentisfree/2008/aug/25/olympics2008.china,” Guardian, August 25, 2008.
2000-09, 2008

Species Conservation in Managed Habitats: The Myth of Pristine Nature (2016), p. 51