“We can assume that in a relatively short time — perhaps within 100 million years — the one celled organism evolved into a colony of cells. With the further passage of time, groups of cells within those colonies assumed specialized functions of food-gathering, digestion, the structural features of an outer skin, and so on; thus began the stage of evolution leading to the complex, many-celled creatures which dominate life today.
The fossil record contains no trace of these preliminary stages in the development of many-celled organisms. The first clues to the existence of relatively advanced forms of life consist of a few barely discernible tracks, presumably made in the primeval slime by soft, wriggling wormlike animals. These are found in rocks about one billion years old. These meager remains are the earliest traces of many-celled animal life on the planet.”

Red Giants and White Dwarfs : Man's Descent from the Stars (1971), p. 249.

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Robert Jastrow3

American astronomer 1925–2008

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“In manufacturing food for its own cells, the plant is producing a supply of food that will be available for the sustenance of animal cells also. Thus the entire animal World may be said to be a vast parasitic colony as absolutely dependent upon the vegetable colony for its essential food supplies as any other parasite is dependent upon its host.”

Luther Burbank (1849–1926) American botanist, horticulturist and pioneer in agricultural science

p, 125
How Plants are Trained to Work for Man (1921) Vol. 5 Gardening

“For the first half of geological time our ancestors were bacteria. Most creatures still are bacteria, and each one of our trillions of cells is a colony of bacteria.”

Richard Dawkins (1941) English ethologist, evolutionary biologist and author

The Richard Dimbleby Lecture: Science, Delusion and the Appetite for Wonder (1996)

Leonard Hayflick (1928) American anatomist

[How and why we age, 1994, Ballantine Books, 177, https://books.google.com/books?id=E2pHAAAAMAAJ&focus=searchwithinvolume&q=loss]

“It is not a simple life to be a single cell, although I have no right to say so, having been a single cell so long ago myself that I have no memory at all of that stage in my life.”

Lewis Thomas (1913–1993) American physician, poet and educator

A Long Line of Cells : Collected Essays (1990), p. 244

“Cells of all kinds share certain structural features.”

Albert L. Lehninger (1917–1986) American biochemist

Principles of Biochemistry, Ch. 1 : The Foundations of Biochemistry

“Perhaps the most remarkable property of living cells and organisms is their ability to reproduce themselves for countless generations with nearly perfect fidelity. This continuity of inherited traits implies constancy, over millions of years, in the structure of the molecules that contain the genetic information.”

Albert L. Lehninger (1917–1986) American biochemist

Principles of Biochemistry, Ch. 1 : The Foundations of Biochemistry

“What constitutes the primordium of the adult parasite [ Rhizocephala ]? What can be injected through the narrow opening of the dart's hypodermic device? …Imagine going through such complexity as nauplius, cyprid, and kentrogon - and then paring yourself down to just a few cells for a quick and hazardous transition to the adult stage. What a minimal bridge at such a crucial transition! …But other species have achieved the ultimate reduction to a single cell! The dart injects just one cell into the host's interior, and the two parts of the life cyle maintain their indispensable continuity by an absolutely minimal connection - as though, within the rhizocephalan life cycle, nature has inserted a stage analogous to the fertilized egg that establishes minimal connection between generations in ordinary sexual organisms.”

Stephen Jay Gould book Leonardo's Mountain of Clams and the Diet of Worms

Triumph of the Root-Heads, p. 363
Leonardo's Mountain of Clams and the Diet of Worms (1998)

“A cell is a complex structure, with its investing membrane, nucleus, and nucleolus.”

Charles Darwin (1809–1882) British naturalist, author of "On the origin of species, by means of natural selection"

"Pangenesis -- Mr. Darwin's Reply to Professor Delpino" Scientific Opinion (20 October 1869) page 426 http://darwin-online.org.uk/content/frameset?pageseq=1&itemID=F1748b&viewtype=image <br class="br">Detractors sometimes claim Darwin thought that the cell was an undifferentiated mass of protoplasm. This quote proves otherwise. <br class="br">Other letters, notebooks, journal articles, recollected statements

“Each individual is a cosmos of organs, each organ is a cosmos of cells, each cell is a cosmos of infinitely small ones; and in this complex world, the well-being of the whole depends entirely on the sum of well-being enjoyed by each of the least microscopic particles of organized matter. A whole revolution is thus produced in the philosophy of life.”

Peter Kropotkin (1842–1921) Russian zoologist, evolutionary theorist, philosopher, scientist, revolutionary, economist, activist, geogr…

Anarchism: Its Philosophy and Ideal (1896)

“[Another significant aspect of the concept of growth is the distinction that Mesarovic and Pestel draw between "undifferentiated" and "organic" growth. The former type of growth, according to these authors, consists of mere replication of cells by cellular division, usually expotentially, with an increase in quantity alone. The latter type of growth] involves a process of differentiation, which means that various groups of cells begin to differ in structure and function… During and after differentiation the number of cells can still increase, and the organs grow in size, but while some organs grow, others might celine.”

Mihajlo D. Mesarovic (1928) Serbian academic

As cited in: Joel Jay Kassiola (1990) The Death of Industrial Civilization. p. 48
Mankind at the Turning Point, (1974)

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Robert Jastrow3

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