1887

Chapter 2 : Tree of Life

MyBook is a cheap paperback edition of the original book and will be sold at uniform, low price.

Ebook: Choose a downloadable PDF or ePub file. Chapter is a downloadable PDF file. File must be downloaded within 48 hours of purchase

Buy this Chapter
Digital (?) $7.00

Preview this chapter:
Zoom in
Zoomout

Tree of Life, Page 1 of 2

| /docserver/preview/fulltext/10.1128/9781555818159/9781555811631_Chap02-1.gif /docserver/preview/fulltext/10.1128/9781555818159/9781555811631_Chap02-2.gif

Abstract:

We have always contemplated and told stories about our origins. We based our earliest stories on many things—sometimes on religious philosophies and sometimes on observations of the world around us. As scientists improved their powers of observation and discovered the meaning of fossils, however, our older views of the tree of life were shaken, and a new tree emerged. Now scientists are able to look into life's information set—the DNA—and are using it to build yet another tree of life, changing our views once again of how living creatures are related. With our increasing powers of observation, we can see that even our branch of the tree contains the genetic footprints of our earliest ancestors—the primitive microbes that gave rise to all living things today. The tools of modern genetics are revealing evidence that links us all to our common past and are helping us look to our future. Microbes' use of both horizontal and vertical gene transfers may explain the conflicting results in constructing genetic trees of evolutionary relatedness. Like the ribosomal RNA gene, these genes code for some of the biologic functions shared by all living cells that are likely to be at the very roots of life—the processes for making proteins and maintaining and passing along information to subsequent generations.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2

Key Concept Ranking

Bacteria and Archaea
0.5794882
Circular Double-Stranded DNA
0.4188417
Microbial Evolution
0.41330543
0.5794882
Highlighted Text: Show | Hide
Loading full text...

Full text loading...

Figures

Image of Figure 1
Figure 1

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 2
Figure 2

Growing understanding of earth's prodigious age and changeability, and of the significance of fossils, shook earlier views. New representations needed to show how living creatures were all related.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 3
Figure 3

The trilobites, which lived 500 million years ago, are abundant in the fossil record because of their hard shell. More ancient creatures were all made of soft tissues that generally were not preserved in rocks, and so few traces of their existence remain.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 4
Figure 4

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 5
Figure 5

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 6
Figure 6

Modern communities of microbes, growing in mats and called stromatolites, look very similar to ancient stromatolites that became fossilized billions of years ago. These bizarre microbial pillars can be seen in select locations around the world.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 7
Figure 7

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 8
Figure 8

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 9
Figure 9

It seems likely that sometime in the past a few finches migrated from the mainland to an island in the Galapagos. The different types of finch now found on the islands, with beaks adapted to the available food, are descendants of that original pioneer species.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 10
Figure 10

Every cell of every living creature carries within it two basic classes of molecules: information molecules (DNA), which carry life's ideas, and machinery molecules (proteins), which do life's work.

DNA's sequence of four nucleotides is a set of instructions for making life's machinery.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 11
Figure 11

Proteins—thousands of different kinds— are life's infrastructure, machinery, and moving parts. Among their functions is the reading and replication of DNA.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 12
Figure 12

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 13
Figure 13

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 14
Figure 14

The two center pipes, with their switches fully opened, extrude a long thin shape.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 15
Figure 15

Four pipes, with their switches partially opened, create a shorter, thicker shape.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 16
Figure 16

Finch speciation is the result of multiple changes in proteins that guide the development of different body parts.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 17
Figure 17

In reality, proteins, acting as genetic switches, control the amount and location of beak material and thereby its size and shape.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 18
Figure 18

Over their billions of years of existence, microbes have retained their outer shell while working on improvements within. Although these bacteria look very similar, one lives in the human gut, making vitamins; one lives at the bottom of the ocean, “breathing” sulfur; one lives in soil and converts sunlight to energy; and so on.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 19
Figure 19

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 20
Figure 20

Three organisms have slightly different versions of the same gene, each represented below. Compare pairs of sequences and record the number of differences. Which pair of the three are (a) most closely related (the fewest differences) and (b) most distantly related (the most differences)? Comparisons like this help scientists build the genetic trees of life.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 21
Figure 21

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 22
Figure 22

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 23
Figure 23

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 24
Figure 24

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 25
Figure 25

. . .and RNA. The gene for the RNA chain provided the basis for Woese's analyses. It was just the right size to analyze and changed very slowly over time.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 26
Figure 26

1. Woese prepares the 16s ribosomal RNA gene from each organism for analysis.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 27
Figure 27

2. He compares the rRNA genes' nucleotide sequences from different kinds of organisms (8 shown here), identifying the stretches that are alike and those that are different.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 28
Figure 28

Scientists build genetic trees, in actuality, by using computer analyses that compare the rRNA gene's nucleotide sequence from one organism to those of many others. Such analyses yield trees with branches of varying lengths that diverge in different places.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 29
Figure 29

3. He arranges each organism's segments in order from the most common, universally shared color to the least commonly shared colors.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 30
Figure 30

4. By spreading the segments apart, a tree emerges. In this example, scientists would conclude that A and B are more similar and therefore diverged more recently than did A and D.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 31
Figure 31

Early genetic trees divided the living world into two major branches—the prokaryotes and the eukaryotes.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 32
Figure 32

Midway through Woese's undertaking, he discovered a third major branching of the tree. The new tree had a branch for Bacteria, a branch for Eukarya, and a branch for the strange new microbes that lived in the hot vents—the Archaea.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 33
Figure 33

Karl Stetter's long fascination with microbes that thrive in boiling pools and in steaming holes has brought him many times to the island of Vulcanos, off the coast of Sicily.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 34
Figure 34

Hydrothermal vents support communities of organisms that depend on microbes to supply a usable form of energy—microbes believed to be similar to the earliest forms of life on earth.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 35
Figure 35

The hotter the microbe's natural environment, the nearer it sits to the base of the tree, and hence the more similar it is to earth's first life forms.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 36
Figure 36

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 37
Figure 37

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 38
Figure 38

“The distribution of life on the planet is very different than we would have thought it even a decade ago. We know that there's life shot throughout the crust of the planet. Life is in ice, life is in waters of boiling temperatures.”

—Norman Pace

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 39
Figure 39

Breaking open a bacterial cell frees its DNA.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 40
Figure 40

Pace realized that he could produce beakers full of DNA and analyze it directly without having to grow the microbes in the laboratory.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 41
Figure 41

The number of different sequences of ribosomal RNA genes found in Pace's samples meant that there were an astonishing number of different kinds of microbes present.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 42
Figure 42

The discovery of all these new kinds of microbes necessitated adding many new branches to the ribosomal RNA tree of life.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 43
Figure 43

Life's language uses four letters: A, T, C, and G.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 44
Figure 44

These letters fit together in complementary pairs: A fits with T and C fits with G.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 45
Figure 45

A special protein, called polymerase, takes free-floating nucleotides, matches them up, and makes a complementary strand . . .

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 46
Figure 46

. . . resulting in a molecule of DNA.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 47
Figure 47

*Primers pair up with known sites at either end of the strands. Polymerase copies both strands starting from the primers. In a few hours, there are billions of identical copies of the gene.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 48
Figure 48

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 49
Figure 49

The Eukarya—larger cells with a true nucleus (which include animals, plants, fungi, yeast, and protozoa)—branched off from the Bacterial and Archaeal tree some 2 billion years after life got started.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 50
Figure 50

Even the single-celled members of the Eukarya come in widely diverse body designs.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 51
Figure 51

One long, circular chain of double-stranded DNA floats freely inside the bacterial cell.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 52
Figure 52

Inside the eukaryotic cell's nucleus, DNA is spooled up on proteins in structures called chromosomes.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 53
Figure 53

Mitochondria have DNA as well. It is a circular double-stranded chain similar to that found in bacteria.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 54
Figure 54

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 55
Figure 55

1. A parasitic bacterium invades a larger cell.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 56
Figure 56

2. It is able to multiply inside, and begins to share the products of its metabolism with its host.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 57
Figure 57

3. After many generations, invader and host have come to depend on each other, each dividing separately but in concert with each other.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 58
Figure 58

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 59
Figure 59

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 60
Figure 60

Jeon's original amoebae . . .

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 61
Figure 61

adapted over generations to their bacterial invaders . . .

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 62
Figure 62

until both came to depend on each other.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 63
Figure 63

A mushroom is composed of only a few kinds of cells, and each has a different function.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 64
Figure 64

A penguin is composed of hundreds of different kinds of cells, each kind performing a different function.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 65
Figure 65

Microbes have the unique ability to capture free-floating DNA from their environment. Such a practice can lead to the acquisition of new genetic traits.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 66
Figure 66

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 67
Figure 67

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 68
Figure 68

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 69
Figure 69

With multicellular creatures, the practice of passing around genetic information just doesn't work.

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 70
Figure 70

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 71
Figure 71

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 72
Figure 72

Citation: Needham C, Hoagland M, McPherson K, Dodson B. 2000. Tree of Life, p 45-88. In Intimate Strangers. ASM Press, Washington, DC. doi: 10.1128/9781555818159.ch2
Permissions and Reprints Request Permissions
Download as Powerpoint

References

/content/book/10.1128/9781555818159.chap2

This is a required field
Please enter a valid email address
Please check the format of the address you have entered.
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error