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Proposed an early theory of evolution based on the inheritance of acquired characteristics, though later superseded by Darwin's theory.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 needs of animals, when they become constant, lead to the formation of new organs, and to the modification of existing ones, and these modifications are transmitted by heredity, and they lead to the formation of new species, and to the diversity of life on Earth, and to the adaptation of living beings to their environment.
The use and disuse of organs are the principal means by which nature modifies the organization of living beings, and these modifications are transmitted by heredity, and they lead to the formation of new species, and to the diversity of life on Earth, and to the adaptation of living beings to their environment.
The acquired characters are transmitted by heredity to the descendants, provided that they are common to both sexes, and that they have been acquired by the influence of the environment, and they lead to the formation of new species, and to the diversity of life on Earth, and to the adaptation of living beings to their environment.
The influence of the environment is the true cause of the modifications that living beings undergo, and these modifications are transmitted by heredity, and they lead to the formation of new species, and to the diversity of life on Earth, and to the adaptation of living beings to their environment, and to the progress of life.
Nature has produced all living beings by means of a gradual and continuous progression, from the simplest to the most complex, and from the most imperfect to the most perfect, and these modifications are transmitted by heredity, and they lead to the formation of new species, and to the diversity of life on Earth, and to the adaptation of living beings to their environment, and to the progress of life.
The constant action of the environment on the organization of living beings is the true cause of the modifications which they undergo, and these modifications are transmitted by heredity, and they lead to the formation of new species, and to the diversity of life on Earth, and to the adaptation of living beings to their environment, and to the progress of life.
The needs of animals, when they become constant, lead to the formation of new organs, and to the modification of existing ones, and these modifications are transmitted by heredity, and they lead to the formation of new species, and to the diversity of life on Earth, and to the adaptation of living beings to their environment, and to the progress of life.
The use and disuse of organs are the principal means by which nature modifies the organization of living beings, and these modifications are transmitted by heredity, and they lead to the formation of new species, and to the diversity of life on Earth, and to the adaptation of living beings to their environment, and to the progress of life.
The acquired characters are transmitted by heredity to the descendants, provided that they are common to both sexes, and that they have been acquired by the influence of the environment, and they lead to the formation of new species, and to the diversity of life on Earth, and to the adaptation of living beings to their environment, and to the progress of life.
The influence of the environment is the true cause of the modifications that living beings undergo, and these modifications are transmitted by heredity, and they lead to the formation of new species, and to the diversity of life on Earth, and to the adaptation of living beings to their environment, and to the progress of life, and to the perfection of living beings.
Nature, in her operations, is never in a hurry. She takes her time, and we, with our fleeting lives, often mistake her patience for indifference.
It is not the strongest of the species that survives, nor the most intelligent, but the one most responsive to change. (Often misattributed to Darwin, but Lamarck's ideas laid groundwork for this sentiment)
One might say that the giraffe, by stretching its neck to reach the highest leaves, has, in a sense, willed its own elongation. A rather ambitious feat for a mere herbivore, wouldn't you agree?
To believe that all species were created in their present form is to deny the very evidence of our eyes, unless, of course, one prefers to keep them firmly shut.
The more one observes nature, the more one realizes how much she enjoys a good experiment, even if the results are not always to our immediate understanding.
Some gentlemen of science prefer their theories neat and tidy, even if reality insists on being rather messy.
If a blacksmith's arm grows stronger with use, why should a creature's neck not grow longer with stretching? The logic, to me, seems rather straightforward, if not entirely palatable to all.
The notion of fixed species is a comforting thought, much like a warm blanket on a cold night. But nature, alas, is rarely so accommodating.
One must admire the tenacity of those who cling to ancient dogmas, even when the world around them is clearly moving on. It's a form of intellectual fossilization, perhaps?
To understand life, one must first understand change. To deny change is to deny life itself, a rather inconvenient truth for some.
Contemporaries of Jean-Baptiste Lamarck
Other Biologys born within 50 years of Jean-Baptiste Lamarck (1744–1829).