World-famous paleontologist Dr. Robert T. Bakker shares the truth about T. rex

No one knows everything, you tell yourself, but after a conversation with Dr. Robert T. Bakker, Curator for the Morian Hall of Paleontology, you might believe there’s someone out there who does.


The world-renowned dinosaur expert is famous for his energetic and entertaining style, and imagining not only the shape and size and habits of creatures extinct for millions of years, but the entire ecosystems in which they lived. Using his imagination to peer through deep time, Bakker sees things other paleontologists wouldn’t — because he chooses to think “outside the box.” This week, he returns to the Houston Museum of Natural Science for three exciting events, sharing his wealth of knowledge on dinosaurs, natural history and geology.

Bakker arrived at HMNS Tuesday morning and hosted the premier of the NOVA science television event Making North America in the Wortham Giant Screen Theatre. The show airs on PBS this November.

Wednesday night, he hosts his own lecture titled T. rex — The Shocking Truth at 6:30 p.m., also in the Wortham. Bakker says the presentation will raise an eyebrow about the common reputation of the famous Cretaceous carnivore Tyrannosaurus rex.

bob n rex hall-TrexDMNH

“For example, if you time travel, and it’s at night, and you’re just sitting there watching critters, you hear that the best thing to do is to just sit still,” Bakker said. “That’s what we learn from Jurassic Park. That’s just the wrong answer. T. rex will find you instantly, and all your friends, and the driver of the time-traveling minibus.”

T. rex was a “triple threat,” according to Bakker, with strong vision, hearing and smell, and it was a fast runner. As the apex predator of its time, it was an extremely successful hunter. But that’s not all it was good at. Turns out it was a gentle creature, too.

rex tickler exPages_50-51

Parent T. rexes showing affection.

“The T. rex made excellent parents,” Bakker said. “They were excellent partners, both male and female. If you want to choose really doting, effective, feeling, good role-model parents… be a T. rex.

If you’d like to know how Bakker determined this, you’ll have to come to the lecture, he said.

In spite of his love for the T. rex, a species that piques the imaginations of children and adults across the world along with the animal’s arch-nemesis, Triceratops, Bakker’s favorite dinosaur is and always has been Ceratosaurus.

Trex v ttops

T. rex battling Triceratops… and losing.

“It’s smaller, built lower to the ground, had a muscular tail great for swimming, very sharp, knifelike teeth and a horn on its nose,” Bakker said. “In fourth grade, I saw it in a book called The Fossil Book. And I took a shining to Ceratosaurus. The next year, my parents took us on a trip to Washington, D.C.”

In Washington, Bakker saw the fossil for the first time and was amazed.

“That will change your theology when you’re in the fourth grade in New Jersey,” he said.

The dinosaur is rare and the flexibility of its body and shortness of its legs suggest it probably was best suited to leafing through dense forest and marshland to hunt. The rare dinosaur was found with fish and turtles nearby, likely its primary diet, which would explain the tail suited for swimming, Bakker said.

trex headbump

T. rex squaring off with a competitor, using a head-bump as a fighting technique.

While his experience meeting Ceratosaurus affected him deeply, Bakker wasn’t interested in dinosaurs until he read a 1953 Life Magazine feature on paleontology written by Lincoln Barnett that spanned the entire issue, he said.

“It was arguably the most beautifully-written feature article ever written,” Bakker said. “It was this gorgeous safari through time, starting with the tiny microbes of the Cambrian, Brontosaurus, Stegosaurus, the Texas Permian red beds, mammoths. … It wasn’t weird prehistoric monsters. The reader asks how and why did these things evolve? … Things were related. The history of life made sense. And I announced to my startled parents that having read Life Magazine, I’m going to grow up and dig fossils.”

His parents continued to believe his affinity for paleontology was just a passing phase, Bakker said, up until the publication of his first book.

“By gum, they read it, and they finally got it,” Bakker said. “Dinosaurs are a part of the history of life on Earth, not a random monster parade.”

Meet Bakker in person at his lecture Wednesday, Nov. 4. and also this Saturday, Nov. 7 at the HMNS Dino Days event Breakfast with Dr. Bakker. Beginning at 9 a.m. on the Morian Overlook and moving downstairs into the Moran Lecture Hall, children and adults can have a meal with Bakker, share ideas about paleontology, listen to a presentation and have a blast doing a variety of dino activities.

Mark Your Calendars for these events happening at HMNS 11/2-11/8

Bust out your planners, calendars, and PDAs (if you are throwback like that), it’s time to mark your calendars for the HMNS events of this week! 


Film Screening – Making North Armerica with Dr. Robert T. Bakker
Tuesday, Nov. 3
6:00 p.m.
Join Dr. Robert T. Bakker for the premiere event of NOVA’s Making North America television series on the Museum’s giant screen. Airing on PBS this November, this series is a spectacular road trip through a tumultuous deep past that explores three fundamental questions: How was the continent built? How did life evolve here? And how has the continent shaped us? “Ancient Rock Show” begins at 5 p.m. with hands-on activities and demonstrations. This event is sponsored by NOVA.

Lecture – T.rex – The Shocking Truth by Dr. Robert T. Bakker, Ph.D. 
Wednesday, Nov. 4 
6:30 p.m.
Legendary paleontologist Dr. Robert T. Bakker will reveal the untold story of Tyrannosaurus rex, the top predators in deep time. In his popular energetic and entertaining style, Dr. Bakker will the latest theories on how T. rex dominated the Cretaceous before the mass KT extinction. Dr. Robert T. Bakker is curator of paleontology at the Houston Museum of Natural Science. Dino activities begin at 5:30 p.m.

Breakfast with Dr. Bakker
Saturday, Nov. 7
9:00 a.m. – 11:30 a.m.
Treat your little paleontologist to breakfast with world-famous paleontologist Dr. Robert Bakker. This annual FUNdraiser, benefiting HMNS, offers an opportunity for kids to meet Dr. Bakker, watch his entertaining presentation, enjoy a delicious breakfast and participate in dinosaur activities not open to the general public. Dr. Bakker will also sign autographs and copies of his books will be available.

13 Freaky finds at HMNS

Tentacles, bodies and skeletons, oh my! No matter how beautiful or how vital to the history of natural science and life on Earth, some things are just a little freaky. Check out this short list of our top 13 strange, weird and scary artifacts housed in the permanent halls of the Houston Museum of Natural Science.

13. Stone hands


Sculptor Harold van Pelt carved this hand from a solid block of a special mineral. The sculpture is an exact replica of his wife’s hand.

12. Stone skull


Pelt also carved this, a life-sized replica of the human skull, identical to the real thing inside and out. That includes the brain case. The jaw is removable from the skull.

11. Cambrian sea creaturescreep09

They’re soft and squirmy and have strange, meat-eating mouthparts. These guys aren’t around anymore, but you can get up close and personal to these models based on fossils discovered in Cambrian rock layers. Watch a CG video of them swimming in action alongside trilobites and orthoceras in the Morian Hall of Paleontology.

10. Fossilized sea scorpion pincerscreep06

Sea scorpions didn’t always get this big. But when they did, their claws were brutal! Sea scorpions were the apex predator in the Cambrian seas, with a poisonous stinger and these toothy pincers. These in our collection measure about six inches long. Imagine getting pinched by those puppies!

9. A shark that could swallow an elephantcreep07

Megalodon, the largest shark to have ever existed, could swallow platybelodon, a mastodon ancestor, in a single bite. Good thing they’re extinct, or whole ships might go missing.

8. Stuffed bird specimensCreep02

Our preserved specimens of extinct, rare and modern life can be a fascinating walk through taxonomy and the diversity of life on earth. But they’re still treated skins stuffed with cotton. In these specimens, cotton holds the eyes permanently open.

7. Feeding lion


The glass eyes of this preserved lion seem to challenge all who pass. And the severed leg lets us know he means business. What can you say? Life’s hard on the savannah. Keep it real.

6. Floating model orthocerascreep05

This prehistoric mollusk was an ancestor of the modern squid and octopus. In Cambrian rock, their numerous conical shells make this one of the most successful species of the era. And this model, looming overhead, calls to mind that Lovecraftian god of the apocalypse, Cthulhu. (Click the link for Google images if you’re not cool enough to be familiar…)

5. Wall of skullscreep08Nearing the end of the fossil record we find a who’s who of hominids. Homo erectus, australopithecines and Neanderthals included. But it’s pretty disconcerting to stroll around the corner and be confronted by a skull collection of human ancestors staring you in the face.

4. The mummy of General What’s-His-Name


Better than hominid ancestors are those famously well-preserved Egyptian mummies that draw crowds from around the world. This one was a man said to have been a general of the New Kingdom Pharaoh Thutmose III, dating back to 1450 BC. Now that’s an old corpse.

3. The mummy of Neshkhons


I find it more creepy that we know who this body actually was for some reason. Don’t you? This is the mummy of the noble lady Neskhons, who lived during the 21st Dynasty of Egypt, between 1070 and 945 BC. Like many mummies, she was discovered with her most important organs preserved in canopic jars, not including the brain, of course. To ancient Egyptians, the brain was some worthless head-goop.

2. Disembodied head


This mummified head was discovered with a gold-leaf mask, its eyes painted on the outside looking up to the heavens in a symbol of reverence for the gods. The head dates back to between 200 BC and 100 AD.

1. The Aztec god of human sacrifice

creep01In pre-Columbian Mexico, the Aztec empire stretched for thousands of miles with modern-day Mexico City at its heart. Millions were sacrificed to the god Tlahuizcalpantecuhtli (pronounced tlah-wheeze-call-pan-teh-coot-lee) at the top of the Templo Mayor, the great temple in the middle of the city. Sacrifices were beheaded at the top of a tall flight of steps, and the skulls rolled hundreds of feet down to the city floor. The Aztecs believed the sacrifices kept their food and water plentiful, but the scare tactics also made them the most powerful empire of their time.

Come see the freakshow before Halloween, or come in costume to Spirits and Skeletons Halloween night!


A New Branch: How anthropologists added Homo naledi to our family tree

In a well-deserved world-wide wave of publicity, the existence of a new hominid species was announced recently. Fossil hominins were first recognized in the Dinaledi Chamber in the Rising Star Cave system in October 2013. Now, some two years later, and after exhaustive analysis of more than 1,500 bone fragments, the team decided to go public with this first milestone: the identification of a new human ancestor.

A selection of these bones have been scanned and uploaded to the internet. They also wrote up their findings and published them in an open-access source, eLife, rather than more established channels such as Nature or Science. (A brief side note: as can be seen in this video, one of the thirty specialists involved in the initial evaluation of these remains was Viktor Deak, who was part of the Houston Museum of Natural Science’s team putting together the Lucy’s Legacy exhibit as well as the section on human evolution in the museum’s Morian Hall of Paleontology.)


Fossilized bones discovered in Rising Star Cave in South Africa belong to a new species of hominid.

While social media are currently lit up with all kinds of references to this new species, it might be interesting to address this fundamental question: how does one define a new
hominid species? In other words: “Why is naledi called naledi?“

A starting point in this process is to identify a type specimen. Such a specimen is described in great detail, listing the similarities to and differences from closely related species. There is no central authority that decides on the validity of a species. Rather, this depends on the acceptance of such a designation within the scientific world. New discoveries and more information have given impetus to revisit previous species designations and change them.

As a result, “[i]f two type specimens are later determined to belong to the same species, then the first one named takes priority. For example, when it was decided that the 2nd known australopithecine fossil, assigned to Plesianthropus transvaalensis, actually belonged to the same species as the first that name became invalid and all Plesianthropus fossils were reassigned to Australopithecus africanus.


Skull fragments from the holotype specimen show Homo naledi had a brain about the size of an orange.

If it is decided that the fossils previously assigned to a species actually belong to two different species, then the type specimen and any other specimens belonging to the same species as it keep the old name. The other fossils will take the name of whichever specimen among them is first used as a type specimen for a new species definition. An example is Homo habilis (type specimen OH 7); the species Homo rudolfensis, with type specimen ER 1470, consists of fossils formerly assigned to habilis.”

This new species belongs to the genus Homo. Traditionally, one is a member of that genus if the following criteria are met (Since these are set by human researchers, they are subject to periodic re-evaluation):

  • Brain size: at least 600 cubic cm.
  • Possession of language
  • Opposable thumbs and precision grip
  • Ability to manufacture (stone) tools

We all belong to the genus Homo, species sapiens and subspecies sapiens. We are “Humans, wise, wise” or “very smart humans.” (Since we are the humans investigating ourselves and our ancestors, it should not come as a surprise that we have kept the most honorific label for ourselves.)

If we translate Homo naledi into plain English, we can start with naledi. The species was named Homo naledi; ‘naledi’ means ‘star’ in Sotho (also called Sesotho), one of the languages spoken in South Africa.

According to the research team, the definition of the new species was not “based on a single jaw or skull because the entire body of material has informed our understanding of its biology.”

Interestingly, Homo naledi’s brain size is in the 400 to 600 cubic cm range, yet they are considered to be members of the genus Homo. Here is why: “The shared derived features that connect H. naledi with other members of Homo occupy most regions of the H. naledi skeleton and represent distinct functional systems, including locomotion, manipulation, and mastication.”

Homo naledi - brain size - range

Brain size and tooth size in hominins. (Lee R. Berger et al. eLife Sciences 2015; 4:e09560)

Fossil Dating

One aspect currently left unanswered is when Homo naledi lived; the scientists offer what-if scenarios for dates ranging between one and two million years ago, some even more recent. These are just that: scenarios. They do not provide a date, as none exists at this point.

That brings up the question: how does one date a fossil? Knowing when a human ancestor lived helps us understand the affiliations of different species and who might have evolved from whom. Scientists have access to a wide array of dating techniques.


Homo naledi had human-like hands, though smaller than our own.

Radiometric Dating

Several techniques measure the amount of radioactive decay of chemical elements. Known as radiometric dating techniques, these include potassium-argon dating, argon-argon dating, carbon-14 (or radiocarbon), and uranium series. This radioactive decay occurs in a consistent manner over long periods of time. A benchmark concept in using this approach is that of a “half life,” defined as “the time it takes for one-half of the atoms of a radioactive material to disintegrate.” Early hominid sites in Eastern Africa have stratigraphic affiliations with volcanic layers. These layers can be dated with the radiometric dating techniques just described. As we will see below, the situation in Southern Africa is different.

Measuring Stored Electrons

Thermoluminescence, optically stimulated luminescence and electron spin resonance measure the amount of electrons that get absorbed and trapped inside a rock or tooth over time. The application of these techniques to date fossils highlights how the study of human origins truly is a multi-disciplinary effort.

Thermoluminescence “(or TL) is a geochronometric technique used for sediment. The technique has an age range of 1,000 to 500,000 years. The technique is used on sediment grains with defects and impurities, which function as natural radiation dosimeters when buried. Part of the radioactive decay from K, U, Th, and Rb in the soil, as well as contributions from cosmic rays, are trapped over time in sediments. The longer the burial, the more absorbed dose is stored in sediment; the dose is proportional to a glow curve of light obtained in response when the sample is heated or exposed to light from LEDs. Greater light doses indicate an older age.”

Luminescence dating is “a form of geochronology that measures the energy of photons being released. In natural settings, ionizing radiation (U, Th, Rb, & K) is absorbed and stored by sediments in the crystal lattice. This stored radiation dose can be evicted with stimulation and released as luminescence. The calculated age is the time since the last exposure to sunlight or intense heat.”


Homo naledi’s feet appear nearly human.

Finally, “electron spin resonance (ESR) measures the number of trapped electrons accumulated, since the time of burial, in the flaws of dental enamel’s crystalline structure. At sites containing human and animal teeth, ESR can be used to determine how long the teeth have been in the ground, but finding teeth at an archaeological site is unusual, so this dating method is not as common as thermoluminescence or radiocarbon dating.”

Another dating technique altogether is paleomagnetism. It compares the direction of the magnetic particles in layers of sediment to the known worldwide shifts in Earth’s magnetic field, which have well-established dates using other dating methods.

Sites in Southern Africa cannot be dated with techniques outlined earlier. A lot of the fossil remains are found in a stone matrix, rather than on the surface. These fossils can be dated using biochronology. Most often – though not always – hominid remains are found in stratigraphic association with animal bones. Quite often, these animal remains belong to animal species that roamed elsewhere in Africa, where absolute dates are available. In this way, sites that do not have radioactive or other materials for dating can still be given a reliable age estimate.

Finally, one can estimate the time that elapsed since two species separated from a common ancestor. This is based on the concept of a molecular clock. This method compares the amount of genetic difference between living organisms and computes an age based on well-tested rates of genetic mutation over time.  Since genetic material (like DNA) decays rapidly, the molecular clock method cannot date very old fossils. The most ancient DNA that has been retrieved thus far dates back to 300,000 to 400,000 years ago.

There is no doubt that more information will be forthcoming from the Rising Star Cave system in South Africa. Over the last two years, the researchers have literally scratched the surface of what is in the cave. As mentioned earlier, the genus Homo is defined by a number of features. One of these used to be that we buried our dead. This appeared to have happened in this case as well. Once the remains are dated, we will know if this fundamentally human trait extended further back in time than we ever imagined. Or not.