Stealth Frog-oid in the Permian Ponds: The Panzer Mudpuppy and its Sonar

“Ping….ping…..p i n g…..”

We heard it in the U-boat movie Das Boot. And in Run Silent, Run Deep. And in the History Channel special about the Battle of the Atlantic. A single “ping” figures in a plot twist during The Hunt for Red October. The “ping” is the sound of underwater hunting.

It’s the sound of sonar.

When early U-boats threatened to cut off England in 1917, British scientists worked feverishly to invent a way of tracking submerged subs. The answers came in the between-war years.  A machine would emit a metallic “ping” into the water. If there was a large object underwater nearby, the ping would echo back and be amplified by the machine. The time between ping and echo-ping told the distance; the strength of the echo told the direction.

Sonar went to war big time in 1939. Combined with the code-breakers who deciphered U-boat orders sent by radio, plus anti-sub aircraft, the Allies defeated the new U-boat offensives in 1943 and 1944.

What’s that got to do with our new fossil hall?


Our field crews have brought back the largest single fossil ever dug from the Permian Red Beds of north Texas. Check it out:

judy block david temple

It’s the “Judy Block”, a slab of pond sediment 10 feet long and three tons in weight. Inside are dozens and dozens of complete skulls and jaws from a new species of Panzer Mudpuppy. These were bottom-living amphibians, distant cousins of frogs, who crowded onto the riverbeds and ponds all through the Early Permian 295 to 275 million years ago.

And our Judy Block is a dramatic lesson in Nature’s Passive Sonar.

Active Sonar is used by porpoises and whales — they make clicky noises underwater and use the echoes to find food and, in the mating season, each other.

Passive Sonar is more elegant and delicate. The sonar operator doesn’t ping or click — that would give away the operator’s position to enemies. Instead, the passive sonar operator listens with extremely sensitive microphones. The Hunt for Red October demonstrates how submariners avoid making any noise but just listen and listen and listen — every tiny sound being amplified by the best acoustic equipment. The fossils in our Judy Block show Nature’s equipment in the fossil amphibian.

Look at the skull:

hall blog trimtneurocanalcolor

Running across the bones are a system of sonar canals (technical label: “lateral-line canals”). Most fish have those canals today. Many frogs have a similar apparatus. Under the microscope you’d see a marvelous device. Tufts of tiny sensory hairs are clumped together inside jelly capsules (the jelly is secreted by the cells that hold the hairs). The capsules are connected to nerves that run to the brain.

Imagine you are a Permian Mudpuppy and glance at the three scenes here:


You sit still on your pond bottom. You are passive. But your sonar is super-alert. The water is so murky that you can’t see anything. Doesn’t matter. A fish wanders by above your head. It suspects nothing. But the fish’s tail sends out vibration waves through the water. Minute vibrations bump into the sensory hairs in your sonar canals. You’ve got thousands of the hair clusters, and so your brain knows where the fish is swimming and how fast it’s going.

Your fire-control computer in your brain knows instinctively what to do. Wait. Wait … wait … then FIRE!

You twist your head up. You open your jaws wide. The sudden suction draws the fish into your jaws. Chomp! Yum.

Sonar canals were features of most early amphibians. You can see them in the giant Gator-Headed Amphibian, Eryops, that ruled the waterways in the Red Beds times. In the new hall, we will display a complete Eryops across the pathway from the Judy Block.

When you come to the new exhibit, pause at the Judy Block. Stare at the sonar canals. Get lost in a time-travel reverie. Multitudes of those animals lived their lives through millions of years, each generation being successful through the high-tech acoustic machinery.

More than just bones


Frances holding Peewee,
our American Alligator.

Amongst a giant Diplodocus, amazingly beautiful malachite, and Quetzalcoatl – the Aztec god of chocolate – a variety of live animals reside within the museum as educational ambassadors in our Wildlife on Wheels program.  Fire salamanders and an Indonesian White’s tree frog educate children about amphibians.  A Savannah Monitor and Ringneck Dove help demonstrate the diversity of vertebrates.  Every day, Christine and I, along with the aid of our assistant, Ben, take care of over a hundred animals.

Throughout the year, an American Alligator named Peewee comes to our aid, helping us teach hundreds of children about wildlife in Texas and aquatic lifestyles.  Alligators like Peewee (Alligator mississippiensis) can be found in bayous from Florida to Texas. 

Peewee hails from Brazos Bend State Park in Needville, TX (also home to our George Observatory – watch out for his relatives while you’re out there stargazing!).  During a flood, his mother was forced to abandon her nest.  Luckily for Peewee and his siblings, the park rangers came in to collect the eggs and incubate them.  Through permits and an agreement with Brazos Bend State Park, we have been able to care for Peewee in a captive environment for the last 2.5 years.

Mother alligators are devoted to protecting their nests and hatchlings for up to two years before the young are sent on their way.  She listens for their calls when they are hatching and will help them out of their eggs.  She will carry them in her mouth from one place to another for protection or when looking for food.  If the babies feel threatened, they will chirp like a baby bird, calling for their mother’s help.  When full grown, the male alligator can reach up to 13 feet while the female reaches a length of about 8 feet., and they can live to be 35-50 years old in the wild.


A closeup of our very own Peewee!

Peewee’s species is one of two alligator species in the world, the other one being the Chinese Alligator (Alligator sinensis), which is currently listed as critically endangered. Less than 200 individuals are currently left in the wild.  Due to great conservation efforts, the American Alligator has made a great comeback and is no longer on the endangered species list.

Fun fact!  An alligator has about 80 teeth in their mouth at one time.  Over time, the teeth wear down and are replaced by new ones.  Over the course of a lifetime, an alligator can have 2,000-3,000 teeth!

In future posts, we will bring to light many of our animals’ lifestyles and behaviors, funny stories behind the scenes, and a discussion of other zoology-related topics. Let us know what you want to hear!