Noah and the spaceship: evolution for twenty-firstcentury christians

Alexandre Meinesz, How Life Began—Evolution’s Three Genesestranslated by Daniel Simberloff. The University of Chicago Press,Chicago

Ellen Clarke

Received: 9 February 2009 / Accepted: 9 February 2009 / Published online: 22 February 2009

� Springer Science+Business Media B.V. 2009

Abstract Evolution has increasingly become a topic of conflict between scientists

and Christians, but Alexandre Meinesz’s recent book How Life Began aims to

provide a reconciliation between the two. Here I review his somewhat unorthodox

perspective on major transitions, alien origins and the meaning of life, with a critical

focus on his account of the generation of multicellularity.

Keywords Christianity � Major transitions � Panspermia

Meinesz is already known as a popular science author for his work Killer Algae(1999) about the dangerous spread of non-native algae. As a phycologist he is a little

further away from his home territory in this book which attempts the much grander

task of assimilating biology, history and philosophy into the sort of text that would

not look out of place on the bookshelf at Sunday school. This is evolution for the

religious, the book of Genesis rewritten for the modern world. It combines personal

reflections on art with summaries of the latest discoveries in molecular biology and

paleoecology to offer a uniquely spiritual perspective on cutting edge science.

Meinesz claims there have been three distinct geneses or creations in

evolutionary history. One is the origin of bacteria (about which he says surprisingly

little, save that it did not happen on earth). One is the origin by symbiosis of the

eukaryotes—which is actually a rather heterogeneous collection of separate

transitions, including the origins of the nucleus and of sex, supposedly unified by

the common mechanism of symbiosis. The third and last is the origin of

multicellularity. It is not entirely clear what these three ‘events’ have in common,

that could distinguish them from many other candidate transitions such as the origin

of life, the origin of chromosomes, the origin of cell walls, the origin of language, or

E. Clarke (&)

Philosophy Department, University of Bristol, 9 Woodland Road, Bristol BS8 1TB, UK

e-mail: ec5035@bris.ac.uk

123

Biol Philos (2009) 24:725–734

DOI 10.1007/s10539-009-9157-y

the origin of superorganisms or colonies. He distinguishes four fundamental forces

or motors of evolution—mutation, sexual recombination, natural selection by the

environment and mass extinctions or cataclysms. He emphasizes contingency in

evolution, as well as union—the alliances and aggregations that have made the

evolution of complex life possible. Like Gould (and McShea) his emphasis is on a

long term paleontological view of evolution which emphasizes the success and

longevity of bacteria, in contrast to a more progressive or adaptationist view.

Some highlights are worth mentioning—chapter three is devoted to bacteria, in

fact it’s a tribute to them. We learn about their astonishing super-powers, their

incredible diversity and resilience, their unsurpassed dominance in terms of

numbers and longevity on the planet, as well as their indispensability to all other

forms of life. Chapter six looks at controversies in the history of biology regarding

large scale trends and the tempo of evolution with an impressively accessible

treatment of the epistemological problems that paleoecologists face. He explains

how different sources of evidence are collected and combined to try to reconstruct

the history of life, and how the limitations of these sources of evidence constrain

and possibly bias that picture. There is lots of science here—real photos of

specimens and details about dates, combined in a way that lets the reader feel what

it must be like to be at the forefront of science. Chapter nine contains the high point

of the book—the issue of the so-called sixth mass extinction. Here he manages the

difficult task of stirring your passion on an issue that is so well-rehearsed in these

sorts of books that it is difficult to write about without sounding like you’ve simply

copied it all down from some ecological holy book. Yet Meinesz manages to

breathe new life into the topic.

How Life Began would be called a work of popular science, although it is as

much history of science as science, with a good deal of philosophy thrown in as

well, which is a huge amount of ground to cover in just one book. He covers most of

the major debates in recent evolutionary biology and parts of the work are dense and

rich, but other times things are rushed over so fast that I wonder what the lay reader

would really have gleaned from it. The book opens with a motif that runs throughout

the work—a description of a painting of Antoni van Leeuwenhoek by Vermeer,

which Meinesz uses as an illustration of science as he claims it ought to be done—

with one’s attention turned to the infinite and the mysterious but with one’s feet

placed firmly on the ground. All chapters open with some sort of concrete setting, a

personal anecdote or a distant memory recalled, demonstrating the author’s

determination that he does not sound like a distant inaccessible scholar lecturing

from his ivory tower. Meinesz is keen to reassure the reader that his great intellect

does not preclude him from reaching out to mere mortals.

Largely Meinesz’ efforts to inject his story with spiritual and artistic flourishes

left me cold. I found them clumsy and patronising at best. Maybe there are issues of

translation here, or maybe just turns of phrase that only a philosopher would object

to—for example, he claims that the origin of life entails the origin of the first cells

(Meinesz 2008, p. 23). At his worst he is arrogant and chauvinistic—why does he

want to alienate half his readership by interrupting his chapter on bacteria to muse

on the thought of a ‘‘beautiful woman with bare breasts’’ (Meinesz 2008, p. 65)?

Some chapters feel more like random collections of essays than coherent pieces of a

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larger story, and some of it is downright repetitive although his writing is at its

strongest in the most scientific parts, where you feel that he benefits from letting go

of his stiflingly self-conscious desire to sound profound.

Three features of this book make it stand out from the crowd of other books on

the history of life, such as Dawkins’ Ancestor’s Tale or Maynard Smith and

Szathmary’s Major Transitions in Evolution (which Meinesz conspicuously fails to

mention). Firstly, panspermia. Although this book is entitled ‘How Life Began’ it

does not actually treat the origins of life at all, it merely discusses the arrival of life

on earth. Secondly, the emphasis on union—symbioses and endosymbioses.

Meinesz claims that these kinds of relationships represent a revolution, a schism,

under-represented in evolutionary theory and a departure from Darwinian evolution.

Thirdly, and most conspicuously, religion. This is a self-consciously spiritual work

of popular science which some might find jarring. You cannot ignore the religious

content in this book, nor easily separate it from the scientific—in fact a discussion of

the relationship between evolution and Christianity comprises the heart of several

chapters. I’ll discuss all these departures, as well as carrying out a critical

examination of his treatment of one of the more conventional topics—the transition

to multicellularity.

Panspermia (or more properly, exogenesis)

Meinesz devotes a whole chapter to defending the theory that life originated on an

alien planet before seeding earth and it is evidently one of his favourite axes to grind

(although I struggled to find further work on it by him). It is a passionate defence,

using various plausibility arguments as well as giving an impressively clear account

of some fairly convoluted evidence. Meinesz presents evidence from Friedmann

showing that the meteorite ALH84001 dated to around 4.5 bya (and originating on

Mars) contains traces of compounds (magnetite chains) usually only formed by

bacteria. Supporting evidence suggests that there is a very low possibility that such

compounds were formed in abiotic reactions such as mineralization especially since

they were found aligned into perfect ‘necklaces’ just as in our cells. He further argues

against the possibility of contamination of the meteor or samples. Meinesz

acknowledges widespread controversy as to the veracity of these claims, but

attributes it to personal jealousy and conservatism. What mainstream science would

have to gain by sidelining such evidence is not spelt out. This bit reads as a

fascinating insight into the lives (and political battles) of scientists and it would add

up into a reasonable hypothesis if it was not so obviously one-sided and if he showed

at least an awareness of the typical response of most evolutionists to panspermia

theory. Meinesz offers no answer to the ‘So what?’ problem. What difference does it

make? Most evolutionists find panspermia a hypothesis with limited appeal, simply

because it seems to want to side step the mysteries that really get evolutionists going,

by removing them to a more distant location. Panspermia per se does not solve the

problem of how life originated, it simply extends the available time frame and

environment. Meinesz chooses not, after all, to discuss hypotheses about how life

began at all and, like Will Wright’s computer game ‘Spore,’ simply starts at bacteria.

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Unions

Meinesz intends his work to emphasize the power of an oft-neglected force in

evolution—symbiosis. French biology since Portier has tended to pay more

attention to unions in biology than have the anglo-american traditions (see Sapp

1994 for a history), with their greater attention to individuals and to competition,

and that tradition is continued in this most patriotic of books. We are presented with

the Elysia sea slug, hero of Meinesz’ previous book Killer Algae, to illustrate the

manner in which lineages can borrow traits from one another by symbiosis. The slug

apparently preys on Caulerpa, a tropical alga, and ingests the alga’s cytoplasm

without digesting its chloroplasts. It then deposits the chloroplasts under the surface

of its skin where it uses them to produce energy just like a plant ordinarily does. It is

a slug that photosynthesizes. Meinesz tells the tale well and inserts it within a larger

piece on symbioses and the role they have played in major transitions in evolution.

He draws a direct analogy between the sea slug using stolen chloroplasts, and

prokaryotes using engulfed mitochondria to become the first eukaryotes in

Margulis’ endosymbiosis theory.

It is great that Meinesz puts so much emphasis on this defining kind of union in

evolutionary history, and he is honest here in presenting competing hypotheses and

emphasizing the speculative nature of some of the claims. The somewhat dense

material is also aided tremendously by his cheerful little cartoon storyboards. Yet

the details do not all come through crystal clear, and at times this chapter is

muddled, partly because there is just too much in it. For example, the role of

symbioses more generally in evolution is left unclear, so that it seems

indistinguishable from co-evolution, and the text gets muddied up by non-precise

use of terms like ‘individual’ and ‘partner’ which is common but damaging to a

discussion of endosymbiosis. I also take issue with the extent to which Meinesz

wants to claim that symbiosis is a process different in kind from Darwinian

evolution. He declares it a revolution and a new genesis. But these are not

equivalent. Evolutionary transitions in individuality such as the origin of eukaryotes

and of multicellulars do indeed comprise new geneses in that they create objects at

new higher levels of selection, but they are generally perceived as occurring due to

standard Darwinian processes of variation and selection. Symbiosis may count as a

different source of variation than mutation, especially if we insist that not all new

behaviours have genetic mutations underpinning them, but so does lateral gene

transfer, polyploidy and sex. It is true that symbiosis has often not been given a

sufficiently important place in the history of life, but the optimal way to redress this

balance is not to cry revolution.

Many evolutionary histories restrict their examination of aggregations to the

rather prejudicially named ‘problem’ of altruism. The free-rider problem sees no

mention at all within this book. Instead alliances are depicted as unproblematically

synergistic relationships, illustrated with cartoon amoeba smiling even as they

ingest one another.

It is true that even after Margulis’ initially astonishing hypotheses have been

incorporated into mainstream orthodoxy, many biologists still view symbiosis as the

exception to the norm. But would moving symbiosis closer to the spotlight in

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evolutionary writing really constitute the revolution that Meinesz heralds? Is

symbiosis at odds with the neo-Darwinian synthesis? As is common what we have

here is a difference of emphasis, presented as a difference in kind. It is true that

mainstream accounts of evolution focus on the accumulation and natural selection

of mutations. The question we must ask, however, is whether symbiosis constitutes

a phenomenon that contradicts, extends, or fits neatly within, this description. Most

authors would say that while symbiosis may constitute an evolutionary mechanism

of organism construction in addition to the selection of mutation, it does notundermine or contradict traditional Darwinian selection. The problem is that the

theoretical battle fought between adherents of cooperation and mutualism and of

competition and survival of the fittest, is that the two sides were often

misrepresented as sentimental utopians, on one side, and hard-headed realists on

the other. The mundane truth acceptable to all is that natural selection will favour

alliance whenever it offers synergistic benefits that cannot be acquired alone. The

war of appropriate emphasis then turns on the empirical question of how often such

benefits exist, and the answer increasingly looks to be: a lot. To this extent then

Meinesz can be applauded for seeking to secure a more central position for

symbiosis within evolutionary theory, but I fall short of calling such a change a

‘revolution.’

Religion

You cannot escape the religion in this book. Not only does Meinesz constantly refer

to it, but several chapters are specifically dedicated to evaluating science in the light

of belief and vice versa. One might accuse Meinesz of wanting to rewrite TheAncestor’s Tale for theists. Like Dawkins he wants to make the deep of history of

life accessible and exciting for non-scientists, but without the atheistic vitriol for

which Dawkins has become famous. It is not a bad ambition, as I’m sure Dawkins’

name on the cover is enough to prevent many people who would benefit from it

from even opening The Ancestor’s Tale. Meinesz, a Catholic, wants to present

evolutionary theory as something compatible with religion and spiritualism, without

shrinking from the actual hard science. Unfortunately, he lacks Dawkins’ effortless

capacity for bringing science to vivid and colourful life in the mind of the reader. I

am happy to allow that I am not the believing layman at whom this work is aimed

but I still feel it is a shame that scientists feel the need to muddy their work by

associating it with all this metaphysical stuff on which they are not qualified to

pronounce.

Meinesz sets the tone of the book in chapter one when he talks about a friend’s

determination to retain ownership of land in which some of the oldest prehistoric

cave paintings are found. It is a metaphor perhaps for our common ownership of our

past, for Meinesz goes on to discuss the various creation myths and tries to

emphasize that whatever your beliefs, our past is a shared truth to which all of us

remain connected. He mixes palaeontology with bible stories in a way designed to

emphasize our fascination with our origins. He mostly presents the bible stories as

just stories, while the palaeontology is fact, but he demurs sufficiently to leave room

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for people not to feel contradicted. He even presents the standard Catholic line about

God inserting the soul at some critical moment in evolution, by saying ‘‘Present-day

knowledge would surely have led the authors of Genesis to reserve for God alone

the impulse to create the soul’’ (Meinesz 2008, p. 17). It is unsubtle word-weaselry.

He does not call it science, but he mixes his religion in with his science sufficiently

closely that only prior knowledge allows the reader to easily tell them apart.

Meinesz spends a long time evaluating evidence for a large scale flood that could

have served as the inspiration for the biblical story of Noah and the Ark, about

which I was tempted to say ‘who cares’ leaving the reader to fill in the obvious

answer. But maybe that’s mean, maybe even ‘non-believers’ can find interest in the

capacity that science gives us to explore the origins of these undeniably important

old myths.

Contingency is the issue that Meinesz keeps coming back to because he seems to

view it as presenting the biggest threat to a religious thought. He settles for Gould’s

line that if we reran the tape of evolution, we would see a radically different

outcome, and asks how much this non-teleological worldview threatens the way in

which theists view the ‘meaning of life’. Meinesz also adopts Gould’s other position

about science and religion being NOMA (non overlapping distinct magisteria;

Meinesz 2008, p. 116) and he states that scientists should stick to their half of the

two ‘Magisteria’ and keep out of metaphysical debates that are best left to theists

(even if he fails to take this particular piece of advice himself). So while the

scientific Magisteria rule that evolution is fundamentally contingent and not goal-

directed, this has no bearing on the separate kinds of arguments that the spiritual

magisterial are going to offer regarding mankind’s purpose in life, or what we can

expect to happen after we die. He criticises intelligent design hypotheses for failing

to distinguish these domains, for letting the scientific picture be dictated to by

religion. He claims that the religious or spiritual domain ought to let science proceed

by its own lights without intruding on or feeling threatened by its discoveries.

Most people simply reject this proposed bifurcation. Atheists reject the idea that

the moral domain is only accessible by believers, while theists probably resent the

idea of having to survive on science’s leftovers. Meinesz puts the religious domain

into a subservient relationship with science that many theists would, I imagine, find

hard to accept. The onus is on religious leaders to adjust their views as science

makes new discoveries, not vice versa. Science and religion are not non-overlapping

domains because we do not know what science will discover in the future so we do

not yet have a properly delineated scientific domain. If this is the case then it is

impossible for religion to be sure it does not pronounce on something which science

will later contradict. Religion is condemned to play second fiddle, playing catch up.

Meinesz certainly is no apologist for creationists, and emphasizes that the bible is

just plain wrong about lots of things and that life really is just ‘‘the result of a long,

pitiless, random struggle for survival in the face of incessant arbitrary decapita-

tions’’ (Meinesz 2008, p. 193). Yet he does not think this necessitates conversion to

atheism, just reinterpretation of scripture. ‘‘Ancient, divine messages can be adapted

to modern knowledge.’’ I’m really one of those atheists who would prefer ‘the

faithful’ to be proper full blooded believers or not at all. Talking about the need to

reinterpret religious texts while simultaneously asserting their truth and divinity

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seems like a textbook recipe for trouble: at least literalists have a limited number of

excuses at their disposal. However, Meinesz does not present his religious views as

justifying or excusing anything. Ultimately he is trying to show that believing in

evolution does not force a person to become a non-believer. And he is probably

right. Nonetheless, his religiosity is bound to raise the hackles of anyoneaccustomed to finding wonderment in nature without having to overlay it with a

greasy coat of magical realism.

Origins of multicellularity

The move to multicellularity is a new genesis because, like Lego pieces, it provides

a new and unlimited way of constructing novel organisms by the addition of

different combinations of pieces in different ways. The creative power of

multicellularity lies in its modularity. Organisms can be created in cumulative

stages, where each stage is robust and can be added to without limit. Meinesz claims

that the move to colonial living was presaged by a change in life style—some

organisms left the surface waters of the oceans and settled on narrow ledges of

continental shelf, where the water is shallow enough that plenty of sunlight filters

through. Here they faced a whole different set of ecological challenges—no longer

required to subfloat, they in fact secured advantage by anchoring themselves to the

floor of their hospitable new home.

Much of this chapter is spent debating a single question—was the transition to

multicellularity a simple case of responding adaptively to a changed environmental

circumstances—i.e., to living on a shallow ledge (the ‘‘convergent evolution

hypothesis’’). Or did the move from open water simply allow a pre-existing capacity

to develop and thrive where the previous environment did not favour it (the ‘‘shared

software hypothesis’’). Meinesz places a lot of importance on comparing these

hypotheses. But what turns on whether those mutations happened before of after the

change in habitat? Even if multicellularity is a new life history trait that appeared in

response to a change of habitat, that trait was made possible by an underlying

genetic architecture (combined of course with various other epigenetic and

environmental conditions). Probably a mutation, or a series of mutations, had to

happen to that architecture before multicellularity was available as a strategy. There

are a few reasons why Meinesz thinks it is important to distinguish between the rival

hypotheses.

Firstly, Meinesz sees the existence of multicellularity in multiple distinct

lineages, but not all lineages, as a fact in need of explanation. A trait such as flying

is present across multiple lineages, including birds and mammals. We say that this

trait is analogous, or has appeared by convergent evolution, because the evolution of

flight in bats took place long after the bat lineage separated from the bird lineage.

On the other hand, we say that possession of a vertebra is a homologous trait across

vertebrates because all vertebrates descend from a common ancestor that had a

vertebra. Meinesz thinks the existence of underlying homologous genetic architec-

ture provides this explanation, but analogy does not, because if multicellularity was

an analogous trait in distinct lineages then we should expect to find it in all lineages

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that have sessile lifestyles. Only the ‘shared software’ hypothesis can explain why

some lineages have not made the transition to multicellularity. This is too strong,

because many things that are evolutionary possibilities fail to happen. Dolphins and

sharks have a convergently evolved aquiline body form that helps them swim

efficiently in water, yet there are no fully aquatic marsupials. However, if the

various lineages diverged before any of them had acquired the mutation necessary

for multicellularity, then we have to suppose that the multicellular lineages all

acquired the necessary mutation independently, which Meinesz seems to think is

less attractive on the grounds of parsimony.

Another reason Meinesz has for advocating the shared software hypothesis is that

offers him a route to coherence with his preferred explanation for the appearance of

life on earth—panspermia. If some but not all organismal lineages possess some sort

of necessary genetic precursor to multicellularity, then Meinesz can say that those

lineages descended from different strains of alien bacteria.

Lastly, it seems that Meinesz prefers the shared software hypothesis because it

allows him to give a scientific explanation that is compatible with a theistic need for

the evolution of man to be inevitable. Meinesz claims that if multicellularity is the

result of some shared software, then ‘‘organisms were pre-programmed to become

multicellular when they became sedentary’’ (164) and multicellularity is a

deterministic phenomenon.

Meinesz wants to believe that multicellularity evolved simultaneously across all

lineages and only after the move to sedentary living, and that examples of

multicellular organisms achieved their multicellular status via a single common

mutation or set of mutations. Yet the most up to date evidence suggests that

multicellularity appeared early and repeatedly, because of a confluence of

environmental, ecological and genetic factors. In a recent review, Rokas 2008

claims that multicellularity is a heterogeneous trait across different lineages but that

it first appeared in filamentous cyanobacteria, appearing in the fossil record 2.5–

2.1 bya. Multicellular eukaryotes appeared soon after the appearance of eukaryotes,

around 1.2 bya, with complex forms appearing 1.0–0.4 bya. Volvocine algae

represent the most recent invention of multicellularity, around 0.05 bya. It is

obvious therefore that complex multicellularity appeared neither rapidly nor

simultaneously an all phyla. Furthermore, Rokas says that ‘‘Not all instantiations of

multicellularity are the same, and they do differ in important details’’ (Rokas 2008,

p. 239). For example, multicellularity in volvox likely evolved after incomplete

separation after cell division, whereas in Dictyostelium it is a result of aggregation.

‘‘Thus any expectation that gene families participating in cell adhesion in the two

lineages would show similar trends would likely be unfounded’’ (Rokas 2008, p.

239). It is now known that Dictyostelium achieve multicellularity using a distinct

array of genetic software from the fungi, plants and animals (Williams et al. 2005).

Research done on Volvocine algae also shows that volvocale multicellularity

differs from metazoan multicellularity precisely because they are underpinned by

distinct genotype–phenotype map structures. V. carteri achieve multicellularity

using a gene RegA to conditionally inhibit chloroplast production in some of their

cells. These cells are then prevented from growing to the size which triggers mitosis,

and so are restricted to somatic functions throughout the lifetime of the group. This

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rather crude way of achieving a division of labour prevents V. carteri from

developing multiple cell types and is offered as an explanation for why the

volvocale transition to multicellularity has not been followed by an explosion of

diversity, as in metazoan lineages (Nedelcu and Michod 2003, 2006). Other

metazoans have achieved multicellularity using a more complex series of mutations

at the cellular level so that different sizes of cell can be produced, and mitosis can be

controlled by independent factors such as cell signalling. The key to the hypothesis

is an explanation for why volvox ran up against these constraints, when other phylas

did not. The answer lies in a peculiarity of volvocine mitosis. While most metazoan

cells divide by binary fission, with one cell splitting to produce two, volvocales have

multiple fission. Binary fission allows you to incrementally increase cell size, for

example. Multiple fission means that mitosis of an adult cell reproduces a whole

multicellular individual.

We can surely imagine similar sorts of constraints might block the possibility of

multicellularity altogether in some lineages, refuting Meinesz’ conjecture that only

a shared software hypothesis could explain the absence of multicellularity in these

lineages. On the other hand it has been found that most of the genetic toolkit

necessary for multicellularity in metazoan lineages is also present in unicellular

ancestors. Genes have mostly been co-opted rather than gained anew, though they

have often dramatically increased in number or gained new functions. Some

components, however, do seem to be genuinely novel innovations. The main genetic

changes concern genes responsible for regulating cell differentiation, cell-cell

signalling pathways and cell adhesion. In the evolution of animal multicellularity,

‘‘gene machinery predated but was co-opted for multicellularity in the time

antecedent to the transition’’ (Rokas 2008, p. 246). In fact if we look to the literature

we find the most up to date consensus is that the whole bilaterian clade—i.e., all the

different animal phyla that evolved from a common sponge or cnidarian ancestor—

share a common genetic toolkit, including ancient hox gene clusters. Geneticists

think that duplications and modifications (tinkering) of these very old genes

underpin all of the modern body plans. The closest relatives of the bilaterians, the

cnidarians and sponges, show intermediate forms of multicellularity/coloniality and

a range of sessile and motile lifestyles.

Multicellularity is a homologous trait in some respects, and an analogous trait in

others. It is interesting to ask what was the relative contribution of extrinsic

(ecological and environmental) and intrinsic (genetic) factors in the origin of animal

multicellularity, but this does not amount to the dichotomy that Meinesz portrays.

The evidence therefore says that to some extent the software did predate the

transition (within this lineage) but to some extent new mutations were needed, as

well as much gene duplication and cooption of function. Meinesz may be

overplaying the importance of analogy versus homology here—the matter turns on

common ancestry, which is a matter of degree (Griffiths 2007 denies this, but on the

alternative developmental view of homology then multicellularity probably is not a

candidate homologue at all). All phyla have a common ancestor (probably, because

they all use the same DNA code) and homology and homoplasy are not sides of a

dichotomy but ends of a continuum, separated by varying degrees of modification,

reflecting deep or more recent ancestry (see Hall 2007). The final question then is

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why Meinesz or anyone else should believe that securing one end or other of this

continuum as the explanation for a trait has any bearing at all on the meaning of

life? Homology looks a long way away from the kind of inevitability that theists

really seek.

The epilogue that ends How Life Began serves primarily as a call to arms.

Scientists, Meinesz declares, must leave their ivory towers and face the respon-

sibilities of dissemination and communication of knowledge. Biologists, in

particular, have a duty to guarantee a widespread appreciation of the beauty and

fragility of the world we live in. Whether or not I believe in life after death, I agree

that biologists have a special part to play in ensuring that there is life after

tomorrow.

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Hall BK (2007) Homoplasy and homology: dichotomy or continuum? J Hum Evol 52(5):473–479

Meinesz A (1999) Killer algae. University of Chicago Press, Chicago

Meinesz A (2008) How life began: evolution’s three geneses. The University of Chicago Press, Chicago

Nedelcu A, Michod RE (2003) Evolvability, modularity, and individuality during the transition to

multicellularity in volvocalean green algae. In: Schlosser G, Wagner G (eds) Modularity in

development and evolution. University of Chicago Press, Chicago

Nedelcu A, Michod RE (2006) The evolutionary origin of an altruistic gene. Mol Biol Evol 23(8):

1460–1464

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development. Annu Rev Genet 42:235–251. doi:10.1146/annurev.genet.42.110807.091513

Sapp J (1994) Evolution by association—a history of symbiosis. Oxford University Press, Oxford

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