As a cradle Catholic, I took it as an article of faith to mark conception as the beginning of a human life. But the fact that there was public debate made me assume that science was still investigating the issue of when a new human organism comes into existence.

So when I was a university senior studying animal development, I was astonished that the consensus in biology is so clear and concrete. For any sexually reproducing animal, from fruit flies to humans, the moment in which an egg and sperm merge is developmentally and evolutionarily the point at which a new organism is considered to come into existence. There is no scientific debate on the subject.

Embryos and self-interest

Self-interest is a key concept in this discussion. Every cell acts in its own self-interest, and in a multicellular organism such as a human, that means every cell acts in the interest of the body as a whole. (This concept is taken to its extreme conclusion in Richard Dawkins' book The Selfish Gene.)

Immediately upon fusion of the egg and sperm, a human zygote begins acting in its own self-interest with an event called the cortical reaction, which stops additional sperm from penetrating the egg (which would be lethal). Shortly afterward, it begins secreting hormones to cause its mother's body to allow it to implant in the uterus and gestate it. Every event associated with the embryo has as its aim the continued survival of the embryo, not necessarily the well-being of the mother.

Thus the question of when human life begins is not a semantic one — it is a scientific one, and one that has a known answer.

Science and politics

This is why I felt so much disgust when Congresswoman Diana DeGette falsely declared that science supports the position that it is ethical to kill embryos. Now, in an ironic turn-about, another Congressional Democrat, House Speaker Nancy Pelosi, has made remarks that are in plain contradiction to science.

According to a statement reported on several blogs to have been e-mailed to Catholic bishops, Pelosi justifies her position that a just-fertilized zygote is not a human being on an alleged statement by St. Augustine: "[T]here cannot yet be said to be a live soul in a body that lacks sensation…" (On Exodus 21.22).

Other commentators, from bishops to bloggers, have done an outstanding job of refuting Pelosi's words on theological grounds. Her statement is also unsound on scientific grounds.

Irrespective of whether she is quoting St. Augustine in context (I suspect not), and of whether it accurately reflects Catholic moral teaching on the issue (it clearly does not), her statement blatantly disregards the insights we have from developmental biology.

St. Augustine's statement was an expression of the science of his time, and consists of little more than a definition: a thing that senses has a soul and a thing that does not sense does not have a soul. That view is derived from the classical philosophy of his day.

In modern science, there is no such thing as a natural soul (vitalism having been rejected long ago). The soul is a purely theological concept. While supernatural souls are part of Catholic belief, science is not capable of investigating them.

As for lacking sensation, a freshly fertilized zygote may not have a nervous system, but it does respond to its environment.

Pelosi's remarks on the issue of the beginning of life are ill-informed — not only from a Catholic point of view, but from a scientific one.

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Image: Human ovum before fertilization. Illustration from Gray's Anatomy.

First, a quick note to those reading from a feed: the first post about the Universal Genome was accidentally published before it was ready. As a result, the version you saw in your reader or e-mail contained unfinished sentences and other confusing flaws. Please click here to read the correctly edited version.

That post contained my first impressions of UG. Now I have looked at the paper in Cell Cycle, and I have questions about its scientific value.

I have written and rewritten and unwritten portions of this post, trying to decide what to say about this paper. I researched the journal, which is a relatively new but bona fide biology journal. I searched for other mentions of "Universal Genome" but, except for an Intelligent Design blog or two crowing about this paper, it seems not to have appeared anywhere.

What it boils down to is this: I cannot understand how it passed peer review. There is no place in the theory of evolution for the following statements from the abstract:

(a) the Universal Genome that encodes all major developmental programs essential for various phyla of Metazoa emerged in a unicellular or a primitive multicellular organism shortly before the Cambrian period; (b) The Metazoan phyla, all having similar genomes, are nonetheless so distinct because they utilize specific combinations of developmental programs.

In other words, right before the evolution of the very first animals (metazoans), back when more or less all life on earth was single-celled, some multi-cellular creature appeared that had all the main genes that would be used for all future animals. Somehow its DNA "knew" what genes its descendants would need to grow everything from bilateral symmetry to eyeballs, though it itself presumably had none of these features.

The author, Michael Sherman, is not a zoologist nor an evolutionary biologist; he is a biochemist at a medical college. Thus his qualifications to propose a new theory of evolutionary zoology may be questionable. Still, this paper appeared in a peer-reviewed journal.

Am I missing something here?

No sooner did I post about the blog The Deeps of Time than it introduced me to a concept brand-new to me: the Universal Genome. In a nutshell, UG proposes that all animals have a large, and largely shared, genome; the differences between animal species result from different genes being expressed. Click here for a good explanation of the model, which appeared in a paper in the journal Cell Cycle in 2007.

Unlike evolution, UG really does hypothesize that complexity arose all at once — as if a Boeing 767 had appeared fully formed from a junk yard. In the case of UG, the 767 is the genome, not the phenotype (appearance). A better metaphor would be that the genome is a yard full of every kind of mechanical part one could want, and in each species only certain parts are used.

Clearly, UG fits in very well with Intelligent Design and very poorly with the theory of evolution.

Immediately two problems with this hypothesis jump out at me:

1. Life on earth does not consist solely of animals. I don't believe these genomic observations are found in other kingdoms, such as plants, nor in other domains, such as Bacteria and Archaea. Plant genomes are quite different from animal genomes in terms of what they can contain; for example, unlike animals, plants can easily accommodate many copies of large amounts of the genome, as in polyploidy (multiple copies of chromosomes). Universal genome is not a universal hypothesis if it applies only to animals, meaning some other hypothesis is necessary for other kingdoms of life.

2. Convergent evolution can explain at least some of the observations attributed to UG. For example, the paper notes that cubozoans (box jellies) have eyes that are genetically similar to the eyes of chordates, even though the last common ancestor of cubozoans and chordates did not have eyes. If this observation is true, an alternate explanation is that the eye evolved independently in both lineages from the same genes, genes that happened to be the best suited to the changes that could result in eye genes.

The observations cited in the paper in Cell Cycle hardly require the construction of a brand new theory of dubious scientific value to explain them. Good science would require searching for explanations among existing biological models first.

It has come to my attention that Leave the lights on is not unique. I have discovered another blog on "Science and Catholic faith": The Deeps of Time.

TDOT is a bulletin-style blog, which is something lacking here on LTLO. My approach here is to write articles and essays; TDOT keeps its readers up-to-date on science issues for Catholics, with recent posts on a new source for adult stem cells (wisdom teeth) and Pope Benedict XVI's prayer intention for August (awareness of God's Creation).

Interestingly, TDOT uses an opposite sort of metaphor for its title. But it's worth noting that it also uses "illumination" imagery in its banner logo. My banner shows a light shining down, while TDOT's banner shows a brilliant sunny day lighting up a cathedral.

Be sure to visit TDOT and consider subscribing.

On June 30, 1908, an enormous and apparently spontaneous aerial explosion leveled 80 million Siberian trees near the Tunguska River. Eyewitness descriptions would make the hairs stand up on the back of your neck: a column of blue light moving across the heavens, followed by the "sky split[ting] in two," intense heat, a wall of thunder.

The blast, estimated at 10-15 megatons, has a number of fanciful explanations:

• Perhaps it was a naturally-occurring hydrogen bomb, resulting from the impact of a comet with an unusually large amount of deuterium. Alas, there is virtually no science behind this hypothesis.
• It could have been a black hole passing through the earth — except there was no exit event. A number of science fiction authors have embraced this hypothesis in literature, but fiction is likely all it is.
• Some have speculated it could have been caused by an extraterrestrial chunk of antimatter. But the event left mineral traces, not gamma rays, so this hypothesis is out.

I will not even go into the UFO hypotheses.

Scientists have come to the tentative consensus that the Tunguska event was actually caused by some sort of space object, perhaps a comet or meteor, that entered the atmosphere and exploded in mid-air. It's not an exotic an explanation as some of the ones that have been proposed over the past century, but it is still eye-goggling awesome: It came from outer space!

No crater or large fragments remained after the Tunguska event — only a patch of scorched earth 30 miles in diameter. So scientists have a paltry amount of evidence to investigate. The exact details may never be known.

Further reading:
What Caused the Tunguska Blast? 100 Years Later, Science Still Seeks Answers

I wrote a guest post on DNA computers over at the tech blog Live Crunch. DNA computers aren't computers programmed to interpret DNA. They are computers made of DNA. If that sounds intriguing, head on over for this bulletin style post. For more detail, see an overview, a short history, and an explanation of how it all works.

I've started a new blog for sharing all the useful, nifty, informative, and entertaining miscellany of the web that I feel like sharing. Be sure to stop by Ginkgo100's Picks from the Web some time.

A recent article in Maternal and Child Health Journal found the more culturally Americanized a pregnant Latina woman is, the more likely she is to be suffering from depression. Hispanic women who speak English or were born in the United States scored higher on the Center for Epidemiologic Studies Depression (CES-D) Scale.

Based on the abstract, this article's conclusion appears to be badly flawed. The problem is that the CES-D appears to be focused on measuring depression in people coming from American culture. Depression, curiously, appears different in Latino culture. Somatic (physical or physiological) symptoms are much more common, and may include headaches and stomach problems. The cultural place of women, in particular, may lead them to find it inappropriate to express opinions contrary to those held by people in authority over them, which "obviously may interfere with necessary self-disclosure," according to the Mental Health and Aging Website.

It is possible that in this study, Latinas who were less Americanized experienced depressive symptoms more as physical complaints and less as mental or psychic pain. They also may have felt inhibited from giving completely open responses on the questionnaire, even if they was kept confidential, if those responses might be in conflict to what authority figures (husbands, boyfriends, fathers) expected of them. Women who have internalized American cultural values to a greater extent would be more likely to have high scores on an American depression scale.

The abstract does not indicate whether these issues were addressed in the study. If not, it may show only the predictable result that Americanism leads to a specifically American experience of depression in pregnant Latinas.

Image credit: Maria & Michal Parzuchowski. Some rights reserved.

Scientific American recently interviewed U.S. Congresswoman Diana DeGette (D-Colorado) about her new book, Sex, Science, and Stem Cells. DeGette's book decries opposition to her favorite political pets, those related to human reproduction. Her thesis that this opposition constitutes an attack against science itself is an appalling lie, in which SciAm is blithely complicit. (It's not the only publisher so inclined; "Science and Religion News" glowingly praised the interview.)

The trouble starts right with the title of the interview: "Congresswoman Slams Religious Right's Assault on Science's 'Edgier' Side." "Edgy"? To many scientifically literate people, embryonic stem cell research (ESCR) is vivisection writ very small. Something that unethical can hardly be described with the benign adjective "edgy."

What began in the title grows worse throughout the article. On the second page of the online article, the interviewer asks, "Why did you choose to focus on what you call the "edgier-side" of the big antiscience conspiracy?" This is a classic loaded question, an informal logical fallacy, which makes SciAm's political position crystal clear. Let me refute the assumption behind this question here:

There is no big antiscience conspiracy. The Bush administration is not whispering together with other opponents of (ESCR), "How can we stymie science? Let's count the ways!" In fact, I think one would be hard-pressed to identify even one ESCR opponent who also opposes research that does not involve destroying human beings.

There is no assault against science. Rather, the assault is against particular forms of scientific research that are unethical. ESCR is in the same category as the notorious Tuskegee Study.

ESCR is not about sex. It's about human life: the lives of embryos and the lives of sick people hoping for cures. Research ethics forbid allowing the potential for medical cures to trump the rights of research subjects. It would be just as unethical even if adult stem cell research did not offer potential cures without the ethical thorns.

DeGette declares, "I'm pro-science." She seems to be trying to recouch language to denigrate her opponents, the same way abortion-rights supporters did when they coined the noxious term "anti-choice." There is an implicit lie in DeGette's rhetoric: If you disagree with her political views on ESCR, then you are "antiscience." SciAm should dispense with perpetuating this mendacity and pay no more attention to DeGette.

I am making my way at a sedate pace through NASA astrobiologist Peter D. Ward's book Life as We Do Not Know It: The NASA Search for (and Synthesis of) Alien Life. Astrobiology is the real-world version of what science fiction fans have sometimes called “xenobiology.” Though “astrobiology” means “the study of star life,” Ward doesn't limit the possibility of alien life to other stars or even to other planets. We may not only find alien life on Mars, but even on earth.

The scientific definition of life — little more than an intellectual exercise for most biologists, since they know life when they see it — is the most fundamental problem in astrobiology. We have to know what we are looking for if we are to recognize it.

Ward discusses the history of defining life. Some famous scientists have addressed this question, including more physicists than biologists. One of the first books was What Is Life? The Physical Aspect of the Living Cell by Erwin Schrödinger (yes, the guy who both killed and didn't kill theoretical cats). Ward extensively discusses the criteria developed by Paul Davies, another famous physicist. Davies' book The Fifth Miracle: The Search for the Origin and Meaning of Life lists six qualities that could be expected in any life form: metabolism, organization, development, autonomy, the ability to reproduce, and the ability to evolve. Here are a few thoughts on these qualities.

Metabolism and organization

I grouped these together because they are inseparable. Metabolism is the processing of energy to reduce entropy, and entropy is the opposite of organization. So metabolism preserves organization. And since metabolism requires enormous complexity, organization enables metabolism.

Development

Development is the change in an individual organism over time. I am unconvinced that development, separate from metabolism, is absolutely necessary in the definition of life. Some microbes develop little, if at all, between their asexual “birth” and their reproduction; why should we require it of a microscopic alien creature?

Autonomy

This is the slipperiest of the concepts in the Davies definition of life. Not only is it difficult to pin down exactly what it means (something about “self-determination”), but also exactly how it applies. For example, is a bee hive with a single queen an autonomous unit? Or does that apply to each individual bee in the hive? Or to each cell within each bee? The bee's cells, and the hive's bees, depend respectively on the bee and the hive for their “self-determination.”

Ability to reproduce

Organization means information, so reproduction requires a means to transmit information. Therefore, for any potential life form to reproduce, it needs both a way to reproduce its physical substance and metabolism and the information necessary to organize it. In other words, life needs a genome.

Ability to evolve

I am not sure this item is necessary for the list, not because it is inaccurate, but because of parsimony. The other five qualities can all apply to single organisms, but evolution is something that happens to populations. Metabolism and organization imply variations in efficiency (and therefore competition among members of a population). If reproduction involves any errors or changes in the genome, then logic shows that any population would evolve through natural selection.

Aliens and Origins is an occasional series on Leave the lights on. To make sure you never miss an article in this series, you can subscribe for free.

When I was at university, I worked under the assumption that scientists (some of whom I knew personally, as my professors) were in the business of uncovering the truth of the natural world. Not so, according to the Internet! As a matter of fact, scientists are in the business of hiding the truth, say a staggering number of conspiracy theories.

I just want to know why I wasn't let in on any of these conspiracies. After all, as a student of science, I should have been told what discoveries I had to suppress! Maybe they were saving that for graduate school.

Top 5 conspiracies of science (as found on the Internet):

5. AIDS is not caused by a virus

People die of so-called AIDS because of the toxic effects of AIDS medications. HIV, the virus allegedly responsible for AIDS, is harmless. How do we know? Because there are no "scientific documents" that show HIV causes AIDS. And because a "growing" collection of "bio-medical scientists" says so!

Why the conspiracy? It must have something to do with money, since the website that exposes the conspiracy spells it "AID$".

4. The earth is growing

The earth is growing. Subduction — the meeting of two tectonic plates in which one slides under the other — is impossible according to Science. Yet we have evidence that the opposite of subduction — spreading — does occur. Since the plates undergo spreading but not subduction, the earth is getting bigger and bigger. Q.E.D.

Why the conspiracy? Because this discovery would upset an entire hundred years of science! Just like those other secret discoveries, the photoelectric effect and natural selection! Oh, wait... those weren't kept secret. Wonder why this one was?

3. There are 12 planets in the solar system

Astrologers have known for years that there are really 12 planets revolving around the sun. In 2006, the existence of three new planets was declared by one "Professor H. Cohen," according to T. Stokes, paranormalist. No word what it means to astrology now that Pluto has been redefined as a non-planet. Actually, there is no word about the three new planets, or even about where Prof. Cohen professes, from anyone but T. Stokes.

Why the conspiracy? This one is based on the ignorance of scientists, who could not be bothered to learn about astrology. Out of sad ignorance, they declared it bunk, so they missed out on the astrologers' knowledge.

2. Vaccines contain toxins that are injected right into your bloodstream

The DTaP vaccine, which confers immunity against diptheria, tetanus, and pertussis, contains toxins. Toxins! In fact, it contains toxins from dangerous diseases, including pertussis, tetanus and diptheria!

Why the conspiracy? Toxins! Toxins!

1. The Lucifer Project: Starchild!

Are you prepared.... ....for lots of bad.... PUNCTUATION???? And a video that acknoleges it's speling errors without apollogy? And as one of history's stupid sheeple, are you nevertheless concerned about the next thing on the agenda of the Illuminati after 9/11? 'Cause they are planning to illuminate Saturn by turning it into a second sun!

Why the conspiracy? The Illuminati are going to use the new star to evolve themselves above us "sheeple." How? Well, somehow, of course!

In an old post, I tallied the assorted protests of Pope Benedict XVI's visit to the United States. Expanding on that precedent, I present the 2008 Leave the lights on Awards for World Youth Day Protesters.

The Irony Award

For confusing one's own characteristics with those of the object of one's protest.
Winner: The Green Left for calling Benedict XVI "the reactionary pontiff."

The Most Outrageous Lie Award

For getting it so, so wrong.
Winner: Alex Bainbridge of the Socialist Alliance, who declared that the Church is waging a "war against sex"
Runner-Up: This guy, whose T-shirt reads, "I won't f---- with your gods, you don't f---- with my science"

The Most Childish Complaint Award

For the protest with the tone most akin to a child whining, "He got more pudding than I did!"
Winner: The Australian Greens, a political party, which was upset that the government of New South Wales spent so much on extra police, made road closures, and so forth — all for an event "just for Catholics"

The Most Legitimate Protest Award

For having a good point, even though the thing requested is logistically unrealistic.
Winner: Various victims' advocates who felt the Pope's public apology to sex abuse victims should have been made in personal audiences