In fide constans… Always loyal [Lucy's Legacy]

The model of Lucy created for
the Lucy’s Legacy exhibition.
Photo by reality photography

The Lucy’s Legacy exhibit was reviewed in early February by a representative of the Seattle-based Discovery Institute, which promotes Creationism and Intelligent Design. In the following paragraphs, I would like to add my observations to the statements found in this review.

Let me start with a few general remarks. First, a favorite approach by Creationists is to cast doubt on the subject of evolution, particularly human evolution and to drive a wedge between faith and science. This policy, known as the Wedge Document, is publicly acknowledged by the Discovery Institute as being theirs. Second, a favorite approach of Creationist writers is to represent issues in stark black and white terms.

The 2000-word document is sprinkled with terms that drive the message home: the study of human evolution fails as a belief system; the evidence is scarce and the interpretations fast and loose and not widely accepted. Moreover, some of the evidence is misrepresented.

The writer of the document stated that there is a “paucity of actual hard evidence for human evolution.” An interesting statement, but one which considering the presence of an actual fossilized hominin fossil, fails itself to carry any water. What harder evidence can one want, but for an authentic fossil, I wonder. The same author also quotes a statement that “unless more fossils are recovered (…) there is likely to be a continuing debate on Lucy’s posture…”  Two thoughts come to mind here. It is always good to have more fossil evidence. In fact, for years paleoanthropologists have continued to find fossils every year. Our database of fossilized early humans continues to grow, courtesy of an ongoing scientific effort. This growing database has led to the formulation of answers to old questions while at the same time giving rise to new questions which we need to answer. That is the essence of scientific research; it is a never ending quest for better insights in what we can observe.

These statements, using the terms “paucity” and “until more fossils are recovered,” are misleading. One wonders if the author knows that the remains of 300 Australopithecus afarensis individuals are known to the scientific community, making Lucy and her kind the best known of all of early human ancestors.

Turkana Boy
Creative Commons License photo credit: ideonexus
Turkana Boy

Another lament found in the document is the “incompleteness” of her (i.e. Lucy’s) skeleton.” The author continues “only 40% was found” and “very little useful material from Lucy’s skull was recovered.” I suppose one could say that everything is in the eye of the beholder. Of course, 50% or more would have been even better. However, another way of referring to Lucy and the preservation of her skeleton is that it is amazing that so much was preserved, considering she died more than 3 million years ago. 

Factually incorrect is a statement that “Lucy still represents the most complete known hominid skeleton to date.” There are currently older and better preserved fossils, including some of the same species as Lucy. Baby Selam for example, is much better preserved. More recent than Lucy, but better preserved is an early hominid known as Turkana Boy. Lucy is still the earliest known and most complete adult Australopithecus afarensis. Things were different in 1974, when scientists could say that she was the oldest known and best preserved skeleton of a distant human ancestor. The fact that this statement now has to be qualified to reflect more recent discoveries is a testimony to the dogged work carried out by teams of paleoanthropologists in Africa. It is also an insight that ought to have been included in the Discovery Institute document, as I am sure that this is something they are aware of.

Photo by reality photography

We also get to read that Lucy’s bones were found scattered across a hillside, a vague reference to an old creationist claim that Lucy’s bones do not all belong to the same individual. The fact that this claim has been debunked does not stop creationists from repeating it. The author – it seems – seems to prefer that Lucy’s bones would have been found together as a contiguous skeleton. Aside from the fact that intentional burial did not exist in Lucy’s time and that she did die more than 3 million years ago, it would have been a miracle (pardon the pun) if she had been preserved completely intact and as a contiguous skeleton. One should not, however, raise the reader’s hopes by presenting this a something that should have happened.

I would like to end by referring the author of the Discovery Institute piece as well as all the readers to this latest development: Lucy was scanned at the University of Texas, Austin campus, after the exhibit in Houston had ended. I have no doubt that scientists will be pouring over this new dataset and that this effort will result in improving our understanding of who we are and where we came from.

Loyalty to a cause is admirable; having the ability to see countless shades of grey instead of only black and white is even more desirable.

A Trick or a Treat?

In less than a week, people all over the country, including right here at our museum, will be celebrating Halloween. Perhaps your workplaces and schools are already festooned with ghosts, skeletons, graveyards, and the like.  If you stop and think about it, you may wonder just how it is that we came to celebrate by trying to disguise ourselves or by trying to frighten people.  Is this a trick or a treat?

Picket fence and yellow trees
Creative Commons License photo credit: joiseyshowaa

The short answer as to why we celebrate this time of year with images of death is that we are in the middle of autumn, the season when nature itself is dying.  To fully understand why we celebrate Halloween when we do, we must fully understand the seasons.

Earth orbits the Sun with its axis pointed at the North Star, Polaris. As a result, its axis is tilted by about 23.5 degrees with respect to its orbital plane.  This tilt, combined with Earth’s revolution around the Sun, causes the seasons.  If the North Pole leans towards the Sun, the Sun is higher in our sky and we get more direct sunlight.  Also, daytime is longer than nighttime.  As the North Pole begins to tilt away fron the Sun, the Sun appears lower and lower across the sky, and daytime gets shorter and shorter.  Eventually, the slanted-in solar rays and short days bring about winter.  Very cold air masses form in the darkened Arctic and begin to move south, some of which can even reach Houston.

Keep in mind that the Earth’s axis does not tilt back and forth; it points at Polaris the whole time.  In June, the North Pole is leaning towards the Sun, but by December, the Earth’s motion has carried it to the other side of the Sun.  The North Pole, still tilting the same way, now leans away from the Sun.

A common misconception is that the Earth is closer to the Sun in summer and more distant in winter, and that is what causes our seasons.  In fact, Earth’s perihelion (closest approach to the Sun) occurs just after the new year (January 1-4), while aphelion (greatest distance from the Sun) occurs around the 4th of July.  Earth’s orbit is an ellipse, but the Earth-Sun distance does not change by enough to affect our seasons.

where are you?
Creative Commons License photo credit: shioshvili

In the cycle of seasons, there are four points of note.  At the March equinox, neither pole is tilted toward the Sun and the Sun is directly overhead at the equator.  The is the vernal (spring) equinox for us and the autumnal (fall) equinox for folks south of the equator.  At the June solstice, the North Pole is tilted as much as possible towards the Sun, and the Sun is overhead at 23.5 degrees North (the Tropic of Cancer).  This is the summer solstice for us and the winter solstice in the Southern Hemisphere.  At the September equinox, once again neither pole tilts toward the Sun, and the Sun is again overhead at the equator.  This is our fall equinox and their spring equinox.  At the December solstice, the North Pole is tilted as much as possible away from the Sun, and the Sun is overhead at 23.5 degrees South (the Tropic of Capricorn).  This is the winter solstice for us and the summer solstice below the equator. 

We generally think of these points as the beginning of spring, summer, fall, and winter, but it doesn’t have to be that way.  After all, nothing magically happens with our weather on these dates.  We could just as well consider these points the midpoints of each season.  In that case, the seasons would begin and end at points roughly halfway between the equinoxes and solstices, in early February, May, August, and November.  If the equinoxes and solstices are ‘quarter days,’ the points halfway between them become the ‘cross-quarter days.’

The ancient Celts of Europe appear to have divided their year in precisely that way.  Gauls living in what is now France used a calendar of twelve lunar months with a 13th month added every 2.5 years (similar to the Hebrew calendar today).  Their two most significant months were Gamonios (lunar month corresponding to April/May ), which began the summer half of the year, and Samonios (lunar month corresponding to October/November) which began the winter half of the year.  Julius Caesar noted that daytime followed nighttime in Celtic days.  By extension, the dark (winter) half of the Celtic year preceded the light (summer) half, making Samonios the start of their new year.

The Celts in the British Isles (Irish and Scots) also had festivals aligned with the cross-quarter days.  In early February was Imbolc (or St. Brigid’s day).  Weather predicting traditions of this day are preserved in our current Groundhog Day.  Traditional May Day celebrations are similar to those of the Celtic BeltaneLughnasadh, in early August, marked the start of the harvest. 

'' The Sentiment of Light''
Creative Commons License photo credit: jdl_deleon

The most important, though, was Samhain (pronounced ’sah win’, not ‘Sam Hane’, due to rules of Gaelic spelling), in early November.  This three-day festival marked the beginning of the winter half of the year and the start of the whole year, like Gaulish Samonios.  It was the close of the harvest opened at Lughnasagh, and the time for culling excess livestock.  At this time, the veil between the living and the world of the dead was considered thinner than usual, and people looked forward to meeting and communing with ancestors and relatives who had died.  A ‘dumb supper‘ was set aside for departed relatives.  To scare away unwanted spirits, people dressed in frightening garb.  Note that these spirits were considered unpredictable and possibly mischievous because they were not the familiar ancestors–not because they were particularly evil.  Divination was also practiced at this time, as people sought to predict whom they would marry or how many children they would have. 

Doing the math, you’ve probably figured out that Halloween is not quite halfway from the equinox (September 22) to the solstice (December 21).  But remember, the Celts used a lunar calendar.  They celebrated their festivals on a certain phase of the Moon, possibly full moon, occurring nearest the cross-quarter day.  Upon the adoption of the Julian calendar, which was not strictly lunar, the festivals were moved to the beginning of February, May, August, and November, although this meant they were no longer exactly on the cross-quarter days. 

Creative Commons License photo credit:
The Wandering Angel

In the eighth century AD, Pope Gregory III moved the church’s commemoration of the souls in heaven (All Saints’ Day) from May 13 to November 1.  Another name for All Saints’ Day is All Hallows Day.  (’Hallow’ is an older term for ’sanctify’ or ‘make holy.’  Think of ‘…hallowed be thy name’ from the Lord’s Prayer).  The next day became All Souls’ Day.  The day before All Hallows Day or All Saints’ Day is All Hallows Eve, or Halloween.  The traditions of Samhain, with its similar focus on honoring the dearly departed, were a natural fit for All Hallows Day and All Hallows Eve.

Halloween, then, is ultimately just one expression of the human need to come to terms with death as a natural occurence and to honor those who have gone before.  In the season of the fall of the leaf, with the Sun taking a slightly lower path across the sky each day, the natural world is going through its own ‘death,’ providing a perfect context for our own activities.  We can therefore think of Halloween itself as a treat, not a trick.

I wish everyone a Happy Halloween, with many more treats than tricks.

LEGO: The building blocks of science

Our guest blogger today is Ian Wilkinson, one of the museum’s IT geniuses. Besides being a computer guru, he is an avid science fan and a LEGO enthusiast. Put the two together, and… 

As a life-long fan of both Lego bricks and science, I was thrilled when the announcement for the “Brick Science” contest was posted on one of my favorite Lego fan-sites, Reasonably Clever, this August. The contest had four categories: “Good Scientist”, “Evil Scientist”, “Laboratory Diorama”, and “Real Scientist”. The last category had the most interest for me, and I set about creating a list of the scientists I would like to render in Lego bricks.

Just for fun, I put a few figures together to get started; Thomas Edison, Leonardo da Vinci, the mad scientist Rotwang from the film Metropolis (for the Mad Scientist category). A glow-in-the-dark piece I had recently acquired inspired me to make a Lego Madame Curie, which led to the addition of her husband Pierre and a radioactive research lab.

As I photographed them in normal light, it occurred to me that some “lights out” photos would also be needed to demonstrate the glow effect. While taking photos in the dark, I remembered that I had a black light and wondered how the parts would look under that. The photo turned out rather fuzzy, but looked keen.

While helping Dr. Bakker with some IT issues at work the next day, I decided it would be extra cool to make a Lego version of him for the contest and maybe get him to endorse it by getting photographed with it. That evening, I put together a Lego vignette of Dr. Bakker using a tiny shovel to dig up some animal bones.

I was a bit concerned that the only Lego animal skeleton in my collection is that of a horse, but Dr. Bakker assured me that he has actually dug up horse bones before, and therefore the model was accurate. After selecting the cowboy hat for his figure to wear (there was a fedora available as well), I got a very nice photo of Dr. Bakker holding up his Lego effigy for the contest.

Because only one entry was allowed per category, I had to submit Dr. Bakker under “Real Scientists”, and the Curies as “Good Scientists.” After that, I had to wait until the end of September to find out the contest results.

Finally, the contest winners were announced last Tuesday. I was a bit disappointed that my Dr. Bakker vignette did not win, until I saw the very amusing depiction of “Theoretical Physicist Moog creating fire in the laboratory.” (To see it, click here and scroll down to “Class Four.”) It’s a good thing I took the black light photos of the Curies, as they seemed to appeal to the judges- “Curies in the Lab” won first place for “Good Scientists,” garnering me a Lego kit featuring Lego Alligators!

All in all, it was a very fun contest. I would have been happy not winning a thing; it’s fun to build Lego scientists, especially when I can get the real scientist in on the game! Special thanks to Dr. Bakker for being a good sport and participating in the contest with me!

Spirits & Skeletons 2008

Trick Or Treat Smell My Feet
I know you can get more
creative than this!
Creative Commons License photo credit: peasap

Although Mixers, Elixirs, & IMAX is coming to a close for 2008 it doesn’t mean we’ll stop partying! Seriously, it’s only September. I know it’s kind of crazy to be talking about Halloween, but I know the “What costume am I going to wear for Halloween this year?” conversation is already happening in the back of your head. And it should be!

Join HMNS on All Hallows Eve for the only party in Houston happening in a dinosaur graveyard. We’re going to give you so much more than atmosphere, though. We’ll have The Chromatics pumping out 80s hits all night, world-renowned illusionist Steven Wallach, Fatima and her team of psychics, Bug Chef David Temple, Etoile Arabesque Belly Dance Troupe, hors d’oeuvres, cash bar, and IMAX films. As tradition would have it, we’re going to be having a costume contest as well – so dream up your best outfit for your chance to win our huge grand prize! Don’t miss Spirits & Skeletons, on October 31 from 8 p.m. to 12 a.m. at HMNS!

And, don’t forget that Mixers goes out with a bang tomorrow night, with Grupo Ka-Che – it’s always our biggest party (1,700 last year!) and we’d love to see you there. We’d also love to see your feedback – let us know what you think – and how we can make Mixers even better next year.