Thursday, November 26, 2009


Word of the day: Conflate (v)- to mistake two or more separate things as being only one thing, generally in a way that leads to further logical flaws.

from Latin con- (together) -flate (blow, as in inflate).

I'll give you a few examples of conflation:

There was, some years ago, a debate as to what to call that portion of the American electorate who wanted the US government to be run according to the precepts of the right-wing evangelical clergy in the US. Should they be the Evangelical voters, the Christian Right, the Values Voters? It seemed to many on the political left that we should simply use the word which by definition means, "those who advocate for government according to the rules of a particular religion." This word of course is "theocrats.' Leaders of this movement for Christian government, when asked about the term theocrat would reply that this word comes from Greek theos, meaning god and kratos, meaning rule or regime, and therefore theocracy is direct rule by God, and so they weren't advocating for theocracy, merely rule in the name of and in line with their understanding of the will of God. It is a common trick by those who wish to redefine a word for political or rhetorical purposes to conflate etymology with denotation.

In another example from the news, a large species of Atlantic ray, the flapper skate, has been fished nearly to extinction. It had been conflated with the blue skate, a smaller, faster breeding distinct species, such that for several decades we thought the two species were one, with the flapper skates merely being the larger individuals. As the number of larger individuals declined, no legal protections were put in place, as the relatively numerous smaller individuals indicated reproduction was still sufficient to maintain the population. Oops. Now that the two species have been deconflated, we know that the flapper skate is all but gone.

Finally, on this thanksgiving day, let us not conflate sweet potatoes, which are commonly eaten in North America, with yams, which are not. Whether orange or white, they are sweet potatoes.

So what, you might ask is the difference between conflation and confusion? The answer is that conflation is a specific type of confusion, one that is worth being aware of in its own right. Having a name for a logical flaw, in my experience, makes it easier to spot it.

Wednesday, November 25, 2009

Extinction is evolution

I often enjoy Olivia Judson's science blog on She has an actual science background, and gets the science badly wrong far less often than most other reporters of science.

Her most recent post is more in line with what I expect from science journalism. Without recapping her whole argument, she writes, "But if [evolution] has that much potential — how come organisms keep going extinct in nature? In other words, why does evolution keep failing?"

She then goes on to make a big deal about how evolution fails each time a population fails to evolve. But in so doing she fails to admit the distinction between evolution on the one hand and adaptation on the other.

Evolution is genetic change in lineages with time. Adaptation is the process by which the genetic makeup of a population is altered in a way that helps individuals of that population be more successful in their environment. Adaptation is one mechanism, and result of, evolution. It happens to be the best known mechanism, and the one that in the popular imagination defines evolution. But evolution has lots of other mechanisms. Genetic drift for example. Imagine you have a small population of squirrels on an island, some gray, some black. A disease comes through and kills a significant portion of the squirrels, and even though they are all equally susceptible to the disease, through the randomness of epidemiology more grays than black catch it and die. After the disease, the population has a higher proportion of black alleles than before. The population has evolved, because the proportional genetic makeup of the population has changed. But this is not an example of adaptation, because the genetic change was not caused by one version of the color gene conferring a selective advantage over the other. The allele frequencies "drifted" without being pushed by selective considerations. The next time the disease comes though more black squirrels could happen to catch it, and the allele frequencies could drift back.

So adaptation is not the be all and end all of evolution. Much of the evolution that happens is non-adaptive. And another important mechanisms of evolution is extinction. Imagine now that the disease killed not just some, but all of the squirrels on the island. That population is extinct. They are no longer represented in the genetic diversity of squirrels more generally, of rodents more generally, of mammals more generally. The remaining diversity, through the removal of that population, has changed. The extinct population has ceased evolving, but through their removal the larger group is left genetically less diverse. The genetic makeup of the larger lineage has changed, so evolution has occurred. It is also possible that the residual populations are more fit than the pre-epidemic average, because they are resistant to that particular disease. Whether or not this qualifies as adaptation depends on the fine details of the definition of adaptation you prefer. There is no standardly accepted definition, or rather different groups of biologists prefer different definitions. But all evolutionary biologists, save those who have crossed over into journalism, agree that extinction is an example of, not a failure of, evolution.

Monday, November 23, 2009

Return on Investment in Higher Education

One of the major debates in US politics is usually framed like this: Should we spend more on things that are worth doing, or should we maintain balanced budgets by spending less. The underlying assumption of this type of argument is that spending more necessarily worsens the budget outcome. If the budget outcome income minus spending, doesn't it make sense that spending more worsens the outcome? Only if we can assume that the spending does not spur more income. In other words, only if we assume that investment is impossible. Investment is spending intended to increase income.

After reading Mike Hout's recent article on the importance of public higher education, I was left wondering how public expenditure on higher education compared to other investments in purely budgetary terms. Mike points out that education leads to higher personal incomes, higher rates of entrepreneurship and other good things that increase tax revenues. At the same time education leads to lower rates of things that cost the state money, like imprisonment and needing public assistance through social security/unemployment/health expenditure. So I wondered, how does the expenditure function as a investment. If the state of California could either spend an extra Billion on education, or invest that money in the stock market, how fast would the market have to rise to give better returns than the education (ignoring the non-fiscal benefits of education)?

I wrote to Mike to ask him, and it turns out he is scheduled to give a talk on that very subject here in Rostock some time soon. He sent me a copy of a 129 page report he and colleagues wrote on the subject in 2005. A pdf of that report (or a draft of it) is here.

The concluding summary of the report says:

The state devotes a substantial portion of its budget to supporting education in
California. That support is not wasted: the costs of neglecting education are
high, and the return this investment brings to the state is equally high. Laudable
though it may be, California’s investment in higher education is insufficient. If
things stay as they are now, that is, if future students progress through their
educational careers at the same rates as their ethnic counterparts did in 2000, the
state will suffer a net loss, and that loss will increase as years pass. With no other
changes, the state will forgo revenues from the increased earnings that education
encourages, and pay more to support a population in a situation of increased
poverty and incarceration. If, rather than maintaining the per-person level of
educational support and access, the state were to limit capacity, the situation
would become even more dire.
However, based on existing trends in educational demand, we expect that high
school graduation rates and college going rates will increase, and demands on
state support for education will climb commensurately. California will have to
invest in community colleges and universities in the short run, but both the state
and its residents will benefit handsomely from this additional support in the long
run. Our calculations suggest net savings to the state will exceed the additional cost by three-fold or four-fold, while its population will enjoy lower levels of poverty, crime, and dependency, and higher levels of average income and political participation.

(Emphasis mine)

The report also specifies in great detail the time scale on which these returns occur, and the majority of returns are "realized in the first ten years after investment because the benefits it buys -- lower welfare, less crime, and healthier children -- are problems/ benefits that disproportionately affect 18-34 year olds."

Now this suggests that we are getting 300% return within the first ten years. So let's just say our $1Billion turns into $3Billion by the end of ten years. That is about 11.5% annual return on investment (1.115^10= 2.97), better than the 11% average rise in the Dow Jones from 1926 through to its pre-dot com bust peak in 1999.

I am a strong believer in the value of education, and would gladly quadruple expenditure on education, but I find this purely monetary claim incredible. This is such an extraordinary claim that we are forced to consider the background of the person making it. The only one of the authors I know is Mike, and what I know about him is that he is the Chair of the best Demography graduate program in the Western Hemisphere, a member of the National Academy of Sciences and a careful scholar. Mike does not go around spouting grand pronouncements. If he makes a claim like this it is because his analysis tells him it is true. There really is a strong argument to be made that in purely fiscal terms, investment in higher education pays off better and more consistently than investment in stock.

In that light, two things surprise me. First, that I haven't heard that argument made before. I hang around with a lot of people distraught about the direction American (and particularly Californian) higher education is going, and no one has ever mentioned this. Second, I'm amazed that Wall Street hasn't tried to securitize this yet.

I'm eager to hear what new work on the subject Mike will be presenting at his talk.

Finally, and sadly, I've just heard that Berkeley's demography department won't be able to accept any new graduate students this year. The lack of funding makes it impossible for them to hire faculty to replace those who have retired or left for better funded institutions. If this does not improve in the next few years, I would guess the department will have to close its doors.

Saturday, November 21, 2009


I just got back a paper I submitted last month. They didn't reject it, but they want major revisions. I'm currently too sick to think through exactly what needs to be changed, or rather how little reanalysis and rewriting I can get away with doing. I want it to be a good paper, but I also want to be done with it so I can write other papers. And of course I want it to be published.

Iris also has rewriting and resubmitting to do, so we can be grumpy as a family.

Friday, November 20, 2009

Education, hippies and commies

Iris: This guy is writing about a pipe dream:

Me: True, but it is a good pipe-dream. A well reasoned and researched pipe-dream with a firm empirical basis and deep social wisdom.

Iris: You mean he's a hippy.

Me: Actually, he's the Demography Department Chair at Berkeley.

Iris: Difference?

Prof. Mike Hout's recent piece on Rationing College Opportunity is timely and worth a read. One question he doesn't address, but I will likely write to him and ask: How long does it take for government investment in college level education to budgetarily* repay the government through taxes and avoided expenditures due to all the economic benefits he discusses? I would guess someone has made such an estimate, and if they haven't they certainly should.

The piece was published in The American Prospect. The subtitle of The American Prospect is "Liberal Intelligence" which Iris takes as further proof that only hippies or possibly communists** write for it.

Anyway, Mike writes well and I suggest you give his pipe-dream a read.

* Yes I know that budgetarily isn't a word, but my Grandma Esther, one of the finest kindergarten/1st grade teachers New York City has ever known, told me that because the English Language does so much for us, we have to do what we can for it. Therefore, to her thinking, we have the responsibility not only to use it well, but to give it new words that it should have but somehow doesn't have yet. 'Budgetarily' for example.

** Note that Iris was raised among hippies, and is the only person I know who waxes poetical about Soviet architecture, so she means the terms "communists" and "hippy" in the fondest possible senses. Further note that my Grandma Esther was a socialist with strong communist leanings, and would have agreed with Iris that Prof. Hout sounds like some kind of commie.

Emails from the Chancelor

UC Berkeley is having a bad day:

From: Robert J. Birgeneau, Chancellor
to "Academic Senate Faculty, Staff, All Academic Titles, Other Members of the Campus Community, Students,"
date Fri, Nov 20, 2009 at 9:02AM
subject URGENT: Wheeler Hall

The campus police are working to resolve a protest action that is occurring in Wheeler Hall. Staff, faculty and students who would normally be working in Wheeler Hall are asked to remain out of the building until further notice. Employees who can contact their supervisors should talk to them if possible to determine whether telecommuting or relocation to another work area is an option. Those in the building right now are advised to leave until the situation has been resolved.

Employees who remain on campus may check in at Dwinelle Plaza at 10am. for further information.

Thank you to all of the members of the campus community for your patience in this matter.

And at 10:42AM California time:

Campus police continue to work to resolve the protest action at Wheeler Hall. Campus police are striving to end the occupation of Wheeler Hall with the safety of our campus community, including all those involved in this action, as an uppermost priority.

Wheeler Hall will remain closed until further notice. Instructors who teach in Wheeler Hall will be contacted shortly by e-mail.

And at 11:30 local time:

Approximately 200 protestors are continuing to demonstrate on the south side of campus in the area around Wheeler Hall. Wheeler Hall is occupied by protestors and the building remains locked.

All classes at Wheeler are suspended until further notice and employees who work in Wheeler Hall are advised that they should plan on not being able to enter the building for the remainder of the work day. Employees should confirm alternative work arrangements with their supervisor, as possible. Instructors who teach in Wheeler Hall are being contacted by e-mail.

Fire alarms have been intentionally set off in several buildings including Barrows, Dwinelle, and Sproul Hall. The fire department is verifying that these are false alarms and will allow people to reenter buildings when it is safe to do so.

The safety of our campus community, including those involved in this protest, are an utmost priority of our police as they work to resolve the situation.

Thank you to all members of the campus community for your continued patience in this matter. Please check for updates throughout the day on the Berkeley home page

Wednesday, November 18, 2009

Concepts in the evolution of senescence about which I am increasingly skeptical:

Intrinsic vs. Extrinsic mortality
Optimality hypothesis
Mutation Accumulation hypothesis
Agonistic Pleiotropy hypothesis
Disposable Soma hypothesis
Caloric Restriction Effects
"Rate of living" hypothesis

This list includes most of the theoretical basis for the field

Business trips

I'm being sent for three days in Paris next week. Most of it will be spent touring a laboratory and meeting with the potential collaborators who run it. Still it will be nice to see Paris.

A couple of weeks later I may be going for a meeting in Cologne, to talk with another potential collaborator. Again, it will mostly be work, but it will be nice to see Cologne.

Iris isn't coming with me on either of these business trips, but she may well get a baguette and some cologne out of it.

Hard to know what she will get this weekend on our trip to Hamburg, given that we are vegetarians.

Friday, November 13, 2009

Lunchhour at the Institute

A table full of scientists. Biologists, applied mathematicians, sociologists and demographers. Graduate students and post-docs working for the Institute. Maybe 20 of us, each eating a lunch brought from home. The several conversations are mostly in English, with some German and Italian thrown in for emphasis or clarification. The concert she went to where there were five bands but only four audience members. The hallucinogenic properties of toads and banana peels. The upcoming Kristmasmarkt. The worm in my pear. It takes me several minutes to realize I am the only native English speaker at the table. These several scientists, about half from Germany, have no common language but the language of international science, English. I'm sure glad it isn't German, or I'd be in a different line of work.

Tuesday, November 10, 2009

More musings on individuality and Hydra

It was a trick question. I admit. Well not a trick exactly, but a question to which science does not have a right answer. Even when the question is defined fairly exactly, it isn't clear what unit we should be looking at.

I've already talked a little bit about the hyrda, but I want to give you more detail, because they are such an interesting and bizarre case. There are at least four levels at which we could define the individual in hydra. The smallest is the individual cell. Most cells in a hydra are capable of turning into any kind of hydra cell, producing a whole new hydra, and moving on their own. People have turned a whole hydra body inside out, and the cells that were on the outside just become inside digestive cells, and the cells that were on the outside become skin cells, and the community of cells goes on about its business. Second, the polyp, that thing with the tentacles and digestive system we classically think of as the individual animal. It looks like a little animal. It acts like a little animal (in most ways). It hunts, it reproduces itself, it has different cells doing different jobs. Third, there is the physically attached cluster of hydra. Through budding (growing a new hydra-shaped organism off the side of the old one) hydra reproduce asexually, but the buds get to be a fair portion of the size of the parent before separating, and are generally of almost full complexity while still physically and physiologically attached. One or two or occasionally more buds can be growing off the main polyp at the same time, and one could easily see this mass of genetically identical connected cells as one individual, despite the fact that it has multiple sets of tentacles feeding multiple digestive systems. Finally, one could consider that these genetically identical groups of cells remain part of the same individual even after physical separation. The genetic individual could after a short time encompass many thousands of polyps.

At which of these four levels does senescence occur? We know from experimental evidence that the risk of death by individual cells increases with age, so we have senescence in level one. In level two, the polyp, the experimental evidence points to no senescence, and the same goes for level three. At level four we don't have experimental evidence, but Mueller's Ratchet implies that there would be slow senescence of the genetic individual. Without going into details, Mueller's Ratchet is a line of genetic reasoning which makes clear that the number of harmful mutations in an asexually producing population almost always increases with time, where the number could decrease with sexual reproduction. So as the genetic individual of the hydra keeps producing more polyps, the newer polyps on the average will always have more harmful mutations than those of earlier generations. And remember, just because the polpys don't age doesn't mean they are immortal. They still die, in large numbers, from causes such as being eaten. As the polyps are reproducing and dying, we end up with more polyps from more recent generations and fewer from older generations. The mutational load of the genetic individual increases, and over time this should lead to increased risk of the extinction of the genetic individual. So the genetic individuals, like the cells, senescence, but the two layers of organization in between, the polyps and the clusters, don't.

This is a real problem without a clear solution. Do hydra tell us something important about the evolution of aging, because unlike almost all other animals, they don't age, or are we just looking at the wrong scale?

A more useful way to phrase the question may be to ask why the cell and genetic individual age, but the polp and the cluster don't. The first answer that comes to mind is that both cells and genetic individuals accumulate damage in ways that they can't fully repair, while the polyp and the cluster can easily repair any damage that comes along because any one piece can completely rebuild the whole. In this context, aging occurs when organism are built in a way that doesn't allow for easy repair. At some point this idea will combine with some other idea to form something useful. Or it won't.

Saturday, November 07, 2009

Big obvious idea

I've had a big idea. Actually, its an idea I a couple of years ago, but didn't have the time or resources to pursue. Being at the Institute, where the director can make most anything he want happen, I presented this idea to him, and he wants to make it happen. It is in many ways an obvious idea. When I tell people about it many wonder aloud why they didn't think of it, or think about it's ramifications. My boss says we have to be a little bit careful who and how we bring in collaborators to test and publish this idea, as it is simple and important enough that someone could in theory quickly publish it without us. I'm not used to having to worry about that, and we do need collaborators to test this idea, so I'm checking out potential collaborators' web pages and publications rather than contacting them directly. It is all at a level I'm not used to, and I'm glad to be where I am with the organization I'm in, because they do know how to work this out just right. I'm meeting with the director again on Monday.

And no, I'm not going to tell you what this idea is right now. It combines some blatantly obvious and therefore little examined facts from biology with similarly obvious and under examined facts of demography to come to a surprising (and in retrospect self evident) conclusion of (I hope) great relevance to both fields. The experiments will take some months of pre-organization, and then a few more months to actually do.

ixNay on the ifeLay istoryHay volutionEay

I have been doing a lot of reading of the life-history evolution literature. It turns out there is a lot of it. About 1200 papers are published each year in journals followed by Web of Science using the phrase "life history evolution." These are in a hugely wide range of journals. What I am coming to realize is that the phrase has been overused and broadened to the point that it is nearly meaningless. A study of egg size relative to adult size can be labeled life-history evolution. A study comparing daily activity patterns between males and females can be labeled life history evolution. A study of age at first reproduction can be labeled life-history evolution. Perhaps more troubling for the field, life-history evolution has come to be viewed very much as natural history is. Natural history, the basic facts about what a species does, what the individuals and groups are like, what their habitat is and so on is tremendously important to know when studying a species, but it doesn't get grants, citations or jobs because it is often only relevant to those studying that particular species, and the methods and conclusions are rarely ground breaking. Life history evolution has come to be seen in the same way, likely explaining why there is no journal society or regular meeting for Life History Evolution.

This stigma may help explain why so few biologists wade into the deep rich pools of unasked questions lining the boundaries between evolutionary biology and demography. Such work is quickly labeled as life-history evolution, and despite being novel, important and of general interest, suspected of having the same failings as the rest of the field. The name demographers prefer for this intersection, evolutionary biodemography, does not on the face of it sound like a task for biologists. As I learned from Crayola, green-blue is a type of blue, not a type of green. Evolutionary biodemography is by extension part of demography, not part of biology. This thinking applies despite the fact that many of the publications in evobiodemo are from biologists rather than demographers.

I briefly mentioned some of this to my boss, who is a demographer by training, but one of the leading advocates of the idea that demography and biology need to learn from each other more. He suggested I organize a small conference at the institute, inviting both biologists and demographers. The institute has had these types of meetings before, mostly inviting established people who already blend the two fields, and interesting papers and collaborations have come out of it, but little lasting progress. The people who were already aware of both fields remained aware of both fields, and those who weren't continued not to care. So my thought, now that I've been invited to organize a small conference, is to invite biologists and demographers early in their careers, who work on similar topics, but within their own fields. A few biologists who work on juvenile dispersal patterns, and a few demographers who work on juvenile dispersal patterns, each of which may have little awareness of the fact that other people in the other field wonder about remarkably similar questions. Other sets who work on infant mortality, population responses to natural disasters, cohabitation, etc. Let them present their work, let them make the explicit case of what the other field can learn from them, and then let them present on what they would like to know or get from the other field. A workshop on demography and evolution for early career scientists. I'll add it to my to do list.