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theories rigorously. Here are some of 
my reservations.

One generic problem is that Lynch’s 
evidence comes from broad brush 
comparisons of extremely disparate 
types of organism. It is true that, on 
average, bacteria have much large Ne 
values than most eukaryotes for which 
we currently have data, but they differ 
in numerous other respects as well, 
for example lack of regular sexual 
reproduction. As all good comparative 
biologists know, it is very difficult to 
disentangle cause and correlation 
from wide comparisons. Alternatives 
to many of Lynch’s explanations of 
the patterns can be envisaged, and 
his arguments do not seem to rule 
these out. For example, as he himself 
describes in Chapter 7, the spread 
of transposable elements through 
the genomes of a host population is 
dependent on some degree of sexual 
exchange between members of the 
populations, and the correlations 
described by Lynch could thus at 
least partly be explained by lack of 
such exchange. Furthermore, his 
insistence on the importance of Ne is 
undermined by the fact that models 
of the maintenance of transposable 
elements in intergenic regions (where 
insertions have little direct effects 
on fitness) show that there is no 
difficulty in their establishment in 
very large populations. In accordance 
with this, maize and its relatives are 
chock-a-block full of transposable 
elements, yet have levels of DNA 
sequence variability as large or larger 
than Drosophila species, with their 
relatively low levels of transposable 
elements. 

In relation to the evolution of 
introns, Lynch’s model of their 
origin looks rather strained in 
relation to the evidence that introns 
seem to have been fairly prevalent 
in ancestral eukaryotes, so that 
their rarity and small size in many 
unicellular eukaryotes is a result of 
secondary loss. It is also undermined 
by evidence for high levels of DNA 
sequence diversity in some species of 
multicellular organisms with introns. 
Could it be that the invention of regular 
sexual reproduction made it easier for 
mobile, initially self-splicing introns to 
invade the genome in large numbers? 
This possibility is not explored by 
Lynch, who resorts (p. 261) to the 
untestable hypothesis that there was 
a long period of reduced Ne among 
ancestral eukaryotes. This is getting 

dangerously close to the adaptationist 
just-so stories that he ridicules in the 
final chapter. 

There are other difficulties worth 
mentioning. One is that, despite 
his advocacy of the importance of 
population genetics, use is made of 
only a limited set of the tools available 
in modern population genetics. 
For instance, recent work using 
comparisons of between-species 
divergence and within-species 
variability to detect departures from 
neutrality increasingly suggests that 
much non-coding sequence is under 
selection, yet this is not mentioned. 
Of course, this is not fatal to Lynch’s 
general thesis, as it can always be 
argued that non-selective forces 
established the non-coding sequences 
in the first place, but it does make one 
wonder.

Despite these criticisms, Lynch’s 
book is essential reading for anyone 
interested in this hugely important 
subject. It has provided us with a 
uniquely valuable overview of genome 
evolution, albeit heavily biased towards 
Lynch’s own interpretations. I am 
especially in sympathy with the strong 
statements in the final “Genomfart” 
chapter (the joke is explained on 
p. 364) that “nothing in evolution 
makes sense except in the light of 
population genetics”, and with the 
criticisms of dubious but fashionable 
concepts such as ‘evolvability’. 

It is too early to tell how well Lynch’s 
own ideas will fare in the face of the 
evidence, although the concept of 
‘sub-functionalization’ (by mutational 
loss of different sequence components 
in different members of a set of 
duplicate genes) seems to be receiving 
significant empirical support. There 
are reasons to expect that rigorous 
comparative tests of hypotheses about 
genome evolution will come to be 
based on careful contrasts of related 
taxa, differing in far fewer features 
that those used by Lynch. At present, 
there are too few genome sequences 
of independent pairs of related species 
to make this feasible on a large enough 
scale for there to be much statistical 
power in such independent contrasts, 
but the advent of rapid sequencing 
methods will probably remedy this 
fairly soon.

Institute of Evolutionary Biology, School of 
Biological Sciences, University of Edinburgh, 
Edinburgh EH9 3JT, UK.  
E-mail: brian.charlesworth@ed.ac.uk
Alan Cowey
Alan Cowey graduated in Natural 
Sciences from Cambridge in 1957 
followed by a PhD under Larry 
Weiskrantz. After a post-doc with Bob 
Doty at the Center for Brain Research 
in Rochester, New York, he returned 
to Cambridge as Demonstrator in 
Experimental Psychology and fellow of 
Emmanuel College. After a sabbatical 
year as a Fulbright Fellow at Harvard 
with Charlie Gross, he moved to 
Oxford as the Henry Head Research 
Fellow of the Royal Society and a 
Fellow of Lincoln College. He remains 
in Oxford as Professor, Emeritus, of 
Physiological Psychology. He was 
elected to the Royal Society in 1988, to 
the Academy of Medical Sciences in 
1998, and a member of the Academia 
Europaea in 1989. He was President 
of the European Brain and Behaviour 
Society from 1986–88 and of the UK 
Experimental Psychology Society from 
1990–92. From 1991–1996, directed 
the MRC interdisciplinary research 
centre in Oxford. If asked what he is, 
he replies “a behavioural neuroscientist 
with a special interest in vision and 
ignorance”.

What attracted you to biology in 
the first place? The wrong things. 
I attended the local grammar school 
in Sunderland and had a master who 
was not a particularly good biologist, 
but to an impressionable schoolboy 
seemed like a renaissance man: 
interested in sport, poetry, music, 
drama, art, architecture, politics and 
travel. He taught me how to pole vault. 
If biology was good enough for him, 
it must be fine for me. Once hooked 
I never regretted it. He suggested 
that I should apply for Cambridge 
because it was “the best for science” 
and I obtained a place in 1954, before 
discovering I needed school certificate 
(now O-level) Latin, which I obtained 
by the educationally dubious process 
of acquiring what could be described 
as tourist’s Italian and learning Virgil’s 
Aeneid Book III by heart. I particularly 
liked the fact that biology was so 
diverse and such a complex system 
(a term not in use then) that even a 
student could do an experiment and 
discover something interesting.  
It’s still true. 

Q & A



Current Biology Vol 18 No 4
R142
What is the best advice you’ve been 
given? I read it rather than received 
it, but it is from T.H. Huxley: “Those 
who refuse to go beyond the truth 
seldom get as far as the truth”. That 
was when I realised everything should 
be questioned: God, the Zeitgeist, 
authority, the flavour of the month. It 
was liberating. It makes enemies, but 
no matter. 

What advice would you offer to 
someone starting a career in 
biology? The same advice. But with 
respect to an area of research, I would 
say choose something that is emerging 
rather than retracting. Don’t waste 
your time crossing the i’s and t’s of 
a supervisor who has worked on the 
same problem for years, unless that 
makes you happy. And if possible 
chose a supervisor who will allow you 
independence and even feed you his 
or her best ideas and let you run with 
them. As well, it is usually a good idea 
to change to another laboratory, a 
new set of techniques and a different 
scientific problem after a doctorate. 
Finally, very few people become 
wealthy as a result of their science; if it’s 
wealth you want, do something else. 

If you were starting again knowing 
what you now know, would you 
follow the same career? Definitely. 
Very few other careers allow and 
encourage such intellectual freedom. 

Do you have a favourite paper? 
Yes, but may I crave indulgence and 
mention two in particular. The first is 
one of a pair in Nature, 1953, by Watson 
and Crick, in which they present their 
ideas about the structure of DNA. It was 
arguably the most influential biological 
discovery of the twentieth century. It 
is just over one page long and even its 
companion in the same volume is just 
over two pages. I have recommended it 
to students and post-docs for decades 
as an example of how to communicate 
ideas and findings succinctly and 
lightly. It contrasts sharply with the 
regrettable and increasing modern 
tendency to use phrases such as 
“…here we show for the first time…” 
and “…these important results 
demonstrate…”, and even “…no other 
group has managed to…”. Authors 
have lost sight of the fact that it is for 
readers to make these judgements. 

The second is the brief paper in the 
Lancet, 1940, in which Heatley and 
colleagues reported that penicillin saved 
the lives of four mice given a lethal 
injection of Streptococcus, whereas 
four other mice, injected but untreated, 
swiftly died. The result ushered in 
the era of antibiotics yet only eight 
mice, the minimum for a statistically 
significant difference between the two 
groups, were used. For many years 
I referred to the paper as an illustration 
of exemplary experimental design in 
connection with issues of the ethical 
use of animals in research. Heatley 
knew about refinement, reduction 
and replacement long before the 3Rs 
became fashionable. 

Do you have a scientific hero and 
if so who is he/she, and why? Yes, 
Charles Darwin and I expect I share 
him with many colleagues. To my mind 
he was the greatest biologist of the 
nineteenth century. He was a colossus: 
totally independent, immensely 
perceptive and careful, in no rush to 
publish, staggeringly original, not afraid 
of opprobrium, and nearly always 
right. Alas, for a variety of reasons 
few students now read original works. 
All biologists know about Darwin but 
not many have ever read his books. 
It’s a shame. It’s like studying English 
Literature and not reading Jane Austen. 

What has been your biggest mistake 
in research? In 1962, while working 
in Bob Doty’s lab in Rochester New 
York, I plotted visual area 2 (V2) and 
its topographical relationship with, 
and dependency on, V1 in the squirrel 
monkey. I noticed that if the recording 
electrode was moved rostrally there 
was a prominent, short-latency, visually 
evoked response in the vicinity of the 
caudal superior temporal sulcus. My 
Fellowship was coming to an end and 
although it was extendable, I had a 
job to return to in England, so I did not 
explore it further. It was subsequently 
thoroughly investigated by Allman and 
Kaas (1971) in the Owl monkey, who 
called it area MT (for middle temporal). 
It is also known as the cortical motion 
area and it became, and remains, the 
most studied and the best understood 
of all extra-striate visual areas. I still 
have my lab books from Rochester and 
when I look at them I realise what an 
opportunity I overlooked. I should have 
stayed for another year. 

What is the next big question to 
be answered in your own area 
of research? It is the nature of 
consciousness. As a graduate student 
I was cautioned against discussing 
ideas such as conscious awareness, 
animal consciousness, covert attention, 
implicit knowledge, and the like. In 
my doctoral thesis and in one of my 
first papers (1963), I suggested that 
monkeys with visual field defects 
produced by removing small parts of V1 
might not actually ‘see’ — in the sense 
of experiencing visual qualia — visual 
targets that they could discriminate 
and voluntarily respond to correctly. 
A referee thought that this line of 
argument was unsound because it was 
in principle untestable. But the editor 
allowed the speculation; what else is a 
discussion for? Over a decade later, the 
phenomenon was named ‘blindsight’ 
in neurological patients and, in 1995, 
Petra Stoerig and I demonstrated it in 
monkeys: we devised (oops, I nearly 
said ‘for the first time’) a way of asking 
monkeys whether a flash of light 
in a clinically blind field defect was 
perceptually like the same visual event 
in the normal visual field or whether it 
was a blank. It was the latter. 

Technical advances made since then 
in recording and localising the activity 
of the brain (high density EEG, MEG, 
fMRI) and stimulating the brain (by 
TMS) while subjects perform various 
perceptual tasks mean that what is 
often called the neural correlate of 
consciousness can be pin-pointed. 
But correlates do not explain anything, 
which has to be the next big step. 
Even then the so-called hard problem 
of consciousness — why we have 
consciousness at all or the related issue 
of why the perceptual experience of 
something like long-wavelength light is 
red rather than something else — has 
no satisfactory solution at present. 

In what ways has the electronic 
revolution changed your life as a 
scientist? In many ways, not all of 
them desirable. The ready access to 
information of all kinds is amazing, as 
is the rapid communication between 
scientists. And publishing will continue 
to change as open-access journals 
proliferate and original data can be 
provided for others to analyse and 
evaluate. Having said that, I doubt 
that many of us have the time or 
the need or the desire to rummage 
through the raw data from other labs. 
Scientists also need thinking time 
and there is progressively less of it. 
We are bombarded with electronic 
requests to review papers, assess grant 
applications, provide testimonials, 



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Tail spins
Hummingbirds are not 
considered the most vocal of 
bird groups but many do make 
sounds; while some of these 
sounds are clearly vocal the 
source of some others has been 
less clear. Researchers have now 
found that the distinctive chirp 
of Anna’s hummingbird males in 
the American south- west, during 
dives at speeds of 80 km/h, 
arises from the wind rushing 
through its splayed tail feathers. 
The feathers quiver in the same 
way as a reed in a clarinet 
vibrates when a musician plays 
the instrument to produce a 
musical note. In this way, the bird 
is able to produce a noise louder 
than anything it might try to make 
using its own tiny voicebox.

The feathers quiver in the 
same way as a reed in a 
clarinet

The researchers said it is the 
first time that any bird has been 
shown to make a deliberate noise 
in this way, but they now believe 
that there are several other 
species of hummingbird that can 
sing through their feathers.

“This is a new mechanism 
for sound production in birds,” 
said Christopher Clark at 
the University of California 
Berkeley, lead author of the 
study with Teresa J. Feo. “The 
Anna’s hummingbird is the only 
hummingbird for which we know 
all the details, but there are a 
number of other species with 
similarly shaped tail feathers that 
may use their tail morphology in 
producing sounds,” said Clark.

The researchers used 
high- speed cameras to record 
a male hummingbird’s mating 
display as he dive-bombed 
a caged female or a stuffed 
dummy. The video showed how 
he unfurled his tail feathers for 
a split second at the bottom of 
his dive, which corresponded 
with a short ‘chirp’ lasting about 
60 milliseconds.
comment on essays from students 
in other countries, and — worst of 
all — provide information for incessant 
bureaucratic enquiries that should not 
be taking place at all. Non-compliance 
is rapidly followed by a further enquiry 
or a thinly veiled reprimand for being 
forgetful or hurtful or not attending to 
emails. It is madness.

Is science organised effectively? 
Science can be pricey and the public 
pay for most of it. So scientists are 
accountable. Fortunately most of them 
appreciate this. Some areas of research 
can only be carried out in centres of 
excellence with shared expensive 
facilities, like high energy physics or 
high-field magnetic imaging. However, 
bureaucratic attempts to make diverse 
scientists from different laboratories 
and even nations collaborate in the 
name of efficiency and international 
development are often spectacular 
failures. Scientists usually know who 
best to collaborate with and usually 
manage to do so. And it is important 
that they should like each other. 
Friendship is the best catalyst. 

You study the behaviour of animals 
and humans: are there serious 
ethical issues in doing so? Yes. It 
is possible to exploit the good will of 
human subjects and even to harm 
them physically or mentally. Obtaining 
genuine informed consent from a 
patient is not trivially easy. Fortunately 
the scientific community is aware of 
this and local, national and international 
legislation at least means that research 
proposals are scrutinised and must 
be approved by knowledgeable and 
disinterested bodies. Investigators 
mutter about how long it can take to 
obtain permission to do certain things 
but I have not yet met any investigator 
who thinks that the legislation should 
be swept away. The ethical issues 
involving research on animals are much 
more controversial and depressing. 
Most of the ‘debates’ are little more 
than a heated ritualistic exchange of 
insults, slogans and physical threats. A 
proper discussion of what constitutes 
an animal’s rights, or the nature of pain 
and suffering and how they can be 
detected and minimised, or whether the 
ends ever justify the means, rarely takes 
place except in esoteric books that are 
not widely read. The public debate is 
intellectually impoverished and lacks 
a genuine meeting of minds. In this 
respect little has changed in a century. 
Are you concerned about deliberate 
falsification of results in science? 
It is difficult to say no to this question 
for there are now several well-known 
examples in biology, some of them with 
a high profile especially in medicine. 
But malpractice exists in every 
professional group (the police, lawyers, 
politicians, the military, industry, even 
the priesthood) and all the evidence 
I have is that it is relatively rare in 
biology. A cynic would say that it is rare 
because it usually brings no financial 
or social gain in biology, and the cynic 
might be right. I am more concerned 
with a different kind of falsification, 
namely that many students now use 
electronic data bases to plagiarise 
for their essays, and even for their 
dissertations. Incredibly, when it is 
spotted by sharp-eyed readers or 
software programmes that can now 
detect it, students seem genuinely 
surprised to learn that there is anything 
undesirable about plagiarism. 

Was it difficult to combine a career 
in teaching and research? It was not 
difficult for me, but it might be were 
I starting out now. I liked teaching and 
found that whenever I encountered 
trouble in explaining something it was 
usually because I had not understood 
it properly. So I learnt a great deal 
by teaching. Probably all teachers 
are constantly reminded that there 
are students in the audience who 
are smarter than they are. That way 
I learned much from students and 
post-docs, including ideas for research. 
I might never have embarked on 
transcranial magnetic stimulation were 
it not for two imaginative post- docs. 
But so much of teaching now involves 
non-educational administrative 
duties (reports, student evaluations, 
committees, quality assessments, 
measures to increase transparency, 
up-dating the web site) that research 
has suffered without any clear evidence 
that the education has improved. In 
some respects it has worsened. 

What is your greatest remaining 
ambition in research? To be the first 
rather than the last to recognize when 
mental ossification sets in and I can no 
longer do good research, and to stop at 
that point. 

University of Oxford, Department of 
Experimental Psychology, South Parks Road, 
Oxford OX1 3UD, UK.  
E-mail: alan.cowey@psy.ox.ac.uk

mailto:alan.cowey@psy.ox.ac.uk