About Guest Contributor

From distinguished lecturers to scientific scholars to visiting curators to volunteers to leaders in their respective fields, we often invite guest authors to contribute content to our blog. You'll find a wealth of information written by these fascinating individuals as we seek to expand your level of knowledge with every post.

Ecoteens build model artifacts for Block Party, opening soon

by John Pederson and Marce Stayer

The Aztecs, one of the greatest Mesoamerican cultures, had all the hallmarks of an advanced civilization. One of their most famous structures, the Templo Mayor, graces the Aztec portion of the John P. McGovern Hall of the Americas. It is a fantastic temple complex, the main religious center of the Aztec capital, and is a feat of architectural genius.

Aztec pyramid complete!

A true-color version of a model Templo Mayor will grace the demonstration shelves of Block Party, HMNS’s new interactive exhibit. And it was built by Moran Ecoteens

The Houston Museum of Natural Science is building a new exhibit called Block Party inspired by the materials used in the construction industry. Curated models of exhibit hall pieces (and visitor-submitted ones) will be on display at the new exhibit. So when the Moran Ecoteens were presented the task of making some of them, an Aztec temple was a popular choice. An image of a temple as inspiration was printed out, and we were ready to build…or so we thought.

John and Connor constructing the pyramid

John and Connor solve building support problems while constructing the pyramid.

Turns out, not all toy building blocks are useful for this purpose. And after we grabbed enough bricks to make the first two exterior layers of the temple (e.g. the Step Pyramid at Saqqara has six “layers”), it was all we could do to prevent the third level from collapsing under its own weight. (To save bricks, we had only built the outside of each layer, leaving the inside hollow.) Eventually, over the course of several days, I worked out a system of struts, columns, and crossties to hold the layers together; the hollow inside was now full of scaffolding. This allowed us to construct a model with accurate dimensions, while reflecting realistic building techniques. The Aztec temple walls were stone encased in painted plaster; our temple reflects this with rigid supports enclosed by a decorative outside shell.

John P. and Aztec pyramid 2

John stands with his model Aztec pyramid built from plastic blocks.

Our multicolored model is the prototype of a future model of the Templo Mayor. The new one will be made of realistically-colored bricks and have a simpler brick-laying scheme, more similar to the Aztec inspiration. Hopefully, those who see it will appreciate both the spirit of the Aztec culture and the engineering genius that defines the monument.


Cream of the Science Crop: Becoming an Ecoteen

You might be wondering how you can get involved doing cool projects for the museum like the Block Party demos. Here’s some information and application advice directly from Marce Stayer, director of the Ecoteen program.

The Moran Ecoteens are the museum’s teen volunteer program, open to teens ages 14 to 17 and rising ninth grade through rising 11th grade. Teens may apply beginning in December by sending their contact information to Stayer. You’ll be asked to provide your name, street address, a phone number and an email where they can be reached. The first week in January, information packets and applications are sent out to all who apply. Applicants will be asked to include a résumé, a letter of recommendation from a current teacher and an essay on the teen’s favorite area of science. The essay can be related to artifacts in our permanent exhibit halls, but it doesn’t have to be. If you’re interested, work hard to write well! We always receive more applications than slots available for this very competitive program.

Completed applications are due Feb. 28. As applications are turned in, teens are invited to schedule an interview. The process must be complete by the second week in March.

Dimetrodon skull and skull

Ecoteens built this model Dimetrodon skull for Block Party, as well.

Selected teens are required to volunteer for one two-week session during the summer. Xplorations summer camp runs on a two-week-on, one-week-off schedule and Ecoteens may choose from these two-week sessions. A new Ecoteen is required to volunteer in the classroom as his or her first assignment. At the end of each week, the teen’s performance is graded by his teacher and turned in to me. If his performance is satisfactory, the Ecoteen may volunteer for additional weeks and have opportunities to work in other areas.

In addition to classroom assignments, Ecoteens are trained to work the touch carts and permanent halls throughout the museum and some are allowed to work in the Special Exhibit halls. They are trained by master docents from the adult volunteer guild for these assignments. They also give science demonstrations to the classes during camp sessions. We have movable demos in Chemistry and Physics, we have a catapult and trebuchet demo, and this past summer, one of the Ecoteens wrote a biology demo called “Microscope Safari” and another created a Morse code demonstration.

Lastly, the Ecoteens help the Youth Education department by working on various crafts that are used during camp — wands and hats for Wizard Academy, belts for Star Warriors Academy, plaster footprints, teeth and claws for the various paleo classes, giant T. rex footprint cut-outs, complete skeletons made out of paper bones, and whatever the classes need. We also write and perform the CSI crime scene on Fridays and put on the Wizard Academy Triwizard tournament. In short, we jump in wherever we are needed!

If this sounds like something you’re interested in, now’s the time to ask for an application so you can get started and be competitive. Best of luck!

Editor’s note: John Pederson is a Moran Ecoteen Coordinator and high school student. Marce Stayer’s official title is Director of the Moran Ecoteen Volunteer Center.

A Symbol of Culture: Francs Guinéens Paint a Picture of Life in Guinea

by Kaylee Gund

During a recent visit to the Museum’s offsite collections storage, one carving in particular caught my eye — the Nimba (D’mba). After living in Guinea for over a year, I immediately honed in on the familiar polished wood of the Nimba among the other West African pieces.


The Nimba.

The Nimba is a symbol of feminine power and fertility, carried on someone’s shoulders around the fields to ensure a bountiful harvest. It wasn’t one of the traditions in the region where I lived, but I still saw the Nimba almost every day in my village on the corner of the 5,000 FG (franc guinéen) note.


The Nimba appears on the corner of a 5,000 FG note.

Among many other traditional symbols, the Nimba has become an expression of national pride, as evidenced by the Guinean bank’s use of it on currency and as its logo. Guinean currency is an interesting mix of national and local identity. Each denomination represents a different culturally distinct region of the country, showing important symbols and economic activities for that region.


A gold mining operation appears on the back of a 500 FG note, paying homage to the major source of income for the Siguiri prefecture.

Haute Guinée, the eastern plateau, is featured on the 500 FG, complete with an image of gold mining on the back. A major source of income for the Siguiri prefecture, gold mining was also an occasional source of exasperation for schoolteachers, as our students would often leave for months at a time during a gold rush and “cherchent l’or,” or “search for gold.”


As you’ve probably noticed, the number of zeros behind monetary amounts in Guinea can be a bit intimidating. Pictured above is a whopping 16,600 FG, worth a little over $2 in the U.S.

What can all this money buy?


Bags of clean drinking water are sold for 500 FG each. Drinking water from the well is ill advised, so this is a worthwhile investment at $0.07.


At the peak of mango season, everyone has more fruit than they know what to do with. It spoils fast with no refrigeration, so piles of mangoes are sold for 2,000 FG (less than $0.30).


Prepared food, like this rice with potato leaf sauce, costs between 5,000 and 7,000 FG for a plate (around $1).

So many mundane things require money that it’s easy to forget what an incredible symbol it can be. Guinean currency gives a glimpse into the many traditions of its different regions, and while there is occasionally ethnic strife between groups and the road to democracy is still rocky, the entire nation is unified in using Guinean francs.

Culture is an incredible thing, and we’re lucky enough to have access to a rich treasure trove of it: from Ancient Egypt to the Amazonian rainforest, even the smallest things can hold great significance.

Next time you’re about to spend a dollar, take a look at what’s on it. You might be surprised!

Editor’s Note: Kaylee Gund is in Youth Education Sales at the Houston Museum of Natural Science. During her time in the Peace Corps, Gund was placed in Guinea to teach chemistry in the country’s national language, French.

Spider Crimes: the Worst Halloween Decorations on the Shelf, Scientifically Speaking

by Melissa Hudnall

September comes and I am shaken to the core with fear. I know what’s coming. No, I don’t mean winter, I mean another year of dismembered bodies and deformed figures. Can I handle the pain in their hurt eyes? Then it happens; I see the first hint of a hairy leg. My trepidation is high as I round the corner to see…



Kill… mmeeee…

I am infamous among my coworkers for getting just as upset as I am excited to see Halloween decorations going up. I adore Halloween, but I also love spiders, and this is where my conflict lies. Halloween does not love spiders. I have used my own tarantula so you can compare real treat to the tricks sitting on the shelves.

Let’s go over some spider basics so you too can feel my pain.


Pay attention to the pedipalps and chelicerae; you may not see them again. Pedipalps are for mating and holding food, and chelicerae house the venom and end in fangs, so these are important body parts. Going without these four appendages is like missing your arms, jaws and teeth.


First off, spiders have eight legs. Count the green circles. Only those are legs. Everything else, not legs.


So basically, I ate this cookie to remove this abomination from the world.

Secondly, they have two body segments — not one, not three. The legs are also attached to the front segment, not the back! The front is the cephalothorax, meaning “head thorax” and the back is the abdomen. Attaching the legs to the back is the same as having a leg growing out of your stomach.


I’m going to assume that these were not meant to be spiders with three segments, but rather very clever spider-mimicking ants. If you can have ant mimicking spiders, then surely it must work the other way around.


These look like ladybugs hitching rides on top of spiders.


And come on, people. Even dogs have standards. This chew toy is sub-par.

Lastly, have you ever tried your hardest and just barely missed your goal? I feel like this next spider embodies that moment. He has the correct number of legs, segments, pedipalps, chelicerae, and they’re all attached in the right places! However, SPIDERS DO NOT HAVE BONES!


*Drops the mic.*

Editor’s Note: Melissa Hudnall is a Programs Facilitator for the Youth Education department at the Houston Museum of Natural Science.


Frankenbirds: A True Story of Science and Immortality, or, How to Make Dead Animals Look Alive

by Sabrina Dahlgren

I’d like to first clarify that this is not a “how-to” manual for your creep-tastic Halloween needs. I’m all for phantasmagorical home decor but the average citizen should not be handling animal specimens. Numerous species are protected or their handling is regulated by state and federal authorities. If you don’t have the necessary permits and training please leave the dead stuff alone (or call us).


Order: Piciformes.

With that disclaimer in place, I’d like to boast that my necropsy (animal autopsy) skills have greatly improved in my time at the Houston Museum of Natural Science. As has my taxidermy technique – not a skill set I thought I’d be adding to my resume, but this place is nothing if not constantly surprising.


Order: Strigiformes.

Why is this done at all, you may ask? As a scientific institution, part of our job is to preserve a record of life on Earth, both for edification of the public (think the Farish Hall of Texas Wildlife and the Frensley/Graham Hall of African Wildlife) and for the maintenance of reference collections used in research (our study skin specimens stored off-site).

It may seem like an obvious assumption, but no one wants to store an untreated dead thing in their building, regardless of ventilation and air-conditioning. Dead things rot, rotten things smell bad and a stinky workplace makes for very unhappy employees. So unprocessed specimens are stored in a freezer until the time comes for someone like me to thaw it out and clean it up. The cleaned skin is either made into a display mount or into a study skin, as much data is gathered as possible, and all records and databases are updated to reflect the newest addition.



What a difference strategic feather placement can make! Juvenile Black-Crowned Night Heron. Nycticorax nycticorax.

So what kind of person does this for a living? Am I the modern, non-fiction equivalent of Victor Frankenstein? So glad you asked! Here’s the answer, in brief:

In presentation I lean more towards lab coat and nitrile gloves than I do mad-scientist hair and demented cackling.



The resemblance is uncanny.

My lab consists of a tiny room with two freezers, a small fridge, storage cabinets, a section of counter well-lit by under-cabinet lights, and a sink; not a condenser coil nor galvanic rod in sight.



A Tesla coil would add to the ambiance…

There is no Fritz or Igor to assist; the closest I come is Pandora or Spotify to pass the time. The best and most ironic song I listen to is The Vulture Song from Disney’s The Jungle Book because I am a ridiculous human being and a morbid sense of humor serves well when I do this work, especially in October.

Most of my tools are normal: scalpels, dissecting scissors, probes and pins. Grocery items are also used: cotton balls, Q-tips, hydrogen peroxide, borax, Dawn dish soap, and an impressive amount of paper towels. Some of my tools are a bit unorthodox. Gardening shears have become one my most useful tools. Toothbrushes have become specimen dinglehoppers. You don’t even want to know what I use a teaspoon for. (Hint: It’s a fat scraper. Enjoy that bit of TMI.)


Hair dryer + toothbrush = bird salon.


Regarding the actual preparation:

  • Documentation is key – keep a written record of all observations and data that may have accompanied the specimen. Take pictures for reference. Or just because.
  • Record external data (weight, visible trauma, general condition, etc.).
  • Skin the specimen. You’ll end up with bone only in the lower legs and feet, wing extremities, and the cranium; organs, muscle, and adipose (fat) should be removed.
  • Clean the skin as thoroughly as possible – cleanliness equals longevity and that’s the big goal.
  • Clean the feathers and the exterior of the specimen as needed.
  • Fill the eye sockets with cotton  for a study skin and glass eyes for a mount.
  • Reinforce the length of the body with a dowel, then add in stuffing to re-form the body cavity. If you’re preparing a mount, add wire armature inside first so that it will hold a pose, then stuff.
  • Stitch up any incisions or tears in the skin and brush the feathers back into place.
  • Secure the specimen on a foam board and allow to dry for one to three weeks, depending on the size and condition of the specimen.

Unlike Doctor Frankenstein, I am happy to report that I do not galvanize specimens. The only electricity I use is restricted to the lights and the hair dryer, not for reanimating the bird.



…it better not be alive.

Why is any of this important? Simple. Scientists like data. Scientists like data even more if there are visual references available. If those reference materials preserve individual variations among species, observations and inferences can be made concerning species and larger taxa of organisms. Our collection is, essentially, a 3-D reference library that will serve future generations.

And that’s pretty amazing, if you think about it.

So there you have it: the key components of a specimen preparation specialist.

Scientific background + morbid curiosity + Disney references + off-color humor = Sabrina.


This is an ex-parrot.

And now I’m off to calculate the air speed velocity of an unladen European Swallow (Hirundo rustica).

P.S. Someone has already done the math, and it is beautiful.


…and this is a gratuitous Monty Python reference.

Editor’s Note: Sabrina Dahlgren is a Curatorial Assistant at the Houston Museum of Natural Science, providing help in tracking and maintaining existing and incoming collections to be installed as exhibits or stored for future exposition.