Habits Quote by Charles Darwin

“Species that evolved from a common ancestor are bunched together under the heading ‘genus’ (plural genera).”

— Yuval Noah Harari

“Perhaps if zoologists would contemplate the wide variations presented by many plants of indubitably one and the same species, and the still wider diversities…

— Asa Gray

The fundamental problem in the origin of species is not the origin of differences in appearance, since these arise at the level of the…

— David Lack

“The rules that govern competition between species are (and must be) very different from the rules that govern competition within species.”

— Daniel Quinn

As in all of biology, comparative studies showing differences among species are often helpful for a better understanding of the basic mechanisms; with all…

— John Tyler Bonner

Now when naturalists observe a close agreement in numerous small details of habits, tastes and dispositions between two or more domestic races, or between…

— Charles Darwin

Mere chance ... alone would never account for so habitual and large an amount of difference as that between varieties of the same species.

— Charles Darwin

Splitting and gradual divergence of genera is exemplified very well and in a large variety of organisms.

— George Gaylord Simpson

“the struggle [for existence] almost invariably will be most severe between the individuals of the same species, for they frequent the same districts, require…

— Robert Harris

It is not always the magnitude of the differences observed between species that must determine specific distinctions, but the constant preservation of those differences…

— Jean-Baptiste Lamarck

The chemical differences among various species and genera of animals and plants are certainly as significant for the history of their origins as the…

— Ray Lankester