Jean-Baptiste Lamarck
Proposed an early theory of evolution based on the inheritance of acquired characteristics, though later superseded by Darwin's theory.
Most quoted
"It is not the organs, that is to say, the nature and form of the parts of the body of an animal, which have given rise to its habits and its particular faculties. It is, on the contrary, its habits, its manner of life, and the circumstances in which its ancestors have found themselves, which have, in the course of time, really constituted the form of its body, the number and state of its organs, and, in short, the faculties which it possesses."
— from Philosophie Zoologique, 1809
"Second Law: All the acquisitions or losses wrought by nature on individuals, through the influence of the environment in which their race has long been placed, and hence through the influence of the predominant use or permanent disuse of any organ; all these are preserved by reproduction to the new individuals which arise, provided that the acquired modifications are common to both sexes, or at least to the individuals which produce the young."
— from Philosophie Zoologique, 1809
"It is not the organs, that is to say, the nature and form of the parts of the body, that have given rise to their habits and particular faculties, but it is, on the contrary, their habits, their manner of life, and the circumstances in which the individuals of which the race is formed have found themselves, that have with time constituted the form of the body, the number and state of their organs, and finally the faculties which they possess."
— from Philosophie Zoologique, 1809
All quotes by Jean-Baptiste Lamarck (412)
The truth is often hidden, but it can be discovered through diligent observation.
Nature never does anything in vain.
The study of nature is a source of profound satisfaction.
All the acquisitions or losses wrought by nature on individuals, through the influence of the environment in which their race has long been placed, and hence the influence of the predominant use or disuse of any organ; all these are preserved by reproduction to the new individuals who originate from them, provided that the acquired modifications are common to both sexes, or at least to the individuals who produce the young.
It is not the organs, that is to say, the nature and form of the parts of the body, that have given rise to their habits and particular faculties, but it is, on the contrary, their habits, their manner of life, and the circumstances in which the individuals of which the race is formed have found themselves, that have with time constituted the form of the body, the number and state of their organs, and finally the faculties which they possess.
Nature, in her operations, has always proceeded by degrees, and has never made jumps.
The constant action of the environment on the organization of living beings is the true cause of the modifications which they undergo.
The needs of animals, when they become constant, lead to the formation of new organs.
Time and favorable circumstances are the two principal means employed by nature to bring all her productions into existence.
The more frequently an organ is used, the more it develops and strengthens; the less it is used, the more it weakens and deteriorates.
Nature has produced all animals successively, from the simplest to the most complex, by means of a gradual and continuous progression.
The influence of circumstances is the most powerful cause of the changes that animals undergo.
It is not the form of the body that determines the habits, but the habits that determine the form of the body.
The environment acts on the organization of animals, and this action produces modifications which are transmitted by heredity.
The direct influence of the environment is the true cause of the modifications that living beings undergo.
Nature has produced all living beings by means of a gradual and continuous progression, from the simplest to the most perfect.
The needs of animals, when they become constant, lead to the formation of new organs, and to the modification of existing ones.
The use and disuse of organs are the principal means by which nature modifies the organization of living beings.
The acquired characters are transmitted by heredity to the descendants, provided that they are common to both sexes.
The influence of the environment is the true cause of the modifications that living beings undergo, and these modifications are transmitted by heredity.
Contemporaries of Jean-Baptiste Lamarck
Other Biologys born within 50 years of Jean-Baptiste Lamarck (1744–1829).