She's the Most Famous Paleobiologist You May Not Know

Born Zofia Kielan in Sokołów Podlaski, Poland, on April 25, 1925, she was 14 years old when Germany invaded her homeland during the fall of 1939, setting off World War II. German troops would continue to occupy Poland until January 1945.

Wanting a subservient workforce, the Nazis segregated learning institutions. Non-Germans living in Polish territory were barred from receiving secondary or higher educations.

Yet there were those who defied the edict. From her 2013 book:

Starting in 1943, Kielan-Jaworowska took covert classes through the University of Warsaw. She chose to study zoology.

Earlier in the war, Kielan-Jaworowska had joined a resistance organization known as the "Grey Ranks." They trained her to become a medic; she'd put those skills into practice during the Warsaw Uprising of 1944, a failed attempt to oust the German invaders for good.

Kielan-Jaworowska credited Roman Kozłowski (1889-1977) with kindling her interest in prehistoric life.

A distinguished paleontologist, Kozłowski became one of Kielan-Jaworowska's professors in 1945, after the University of Warsaw resumed normal operations.

Poland has an abundance of marine invertebrate fossils. Ergo, most of Kielan-Jaworowska's early research focused on trilobites, ancient creatures related to horseshoe crabs. While studying these bug-like critters, she earned her Ph.D. in paleontology from the university in 1953. It was during her graduate school years that she met her future husband, radiobiologist Zigniew Jaworowska. They were introduced during a 1950 mountain-climbing trip and tied the knot eight years later.

The year 1953 saw Kielan-Jaworowska join Kozłowski at the Institute of Paleobiology, an organization run by the Polish Academy of Sciences. It was one of the many scientific enterprises that came of age during the Cold War.

Back in the Roaring '20s, the American Museum of Natural History (AMNH) had organized multiple expeditions through the Mongolian Gobi, a land rich in fossils.

By all metrics, the campaigns were successful. AMNH researchers discovered a whole slew of fascinating "new" dinosaurs (such as the now-famous Velociraptor and Protoceratops) from the Cretaceous Period, a stretch of deep time that lasted between 145 and 66 million years ago.

Then geopolitics intervened. Sandwiched between China and the U.S.S.R., Mongolia emerged as a Soviet satellite. Few researchers from Western countries were allowed to visit its bountiful dig sites once the Cold War arrived.

But the situation was different for their counterparts behind the Iron Curtain, as Kielan-Jaworowska found out.

Paleontologist and science communicator Donald Prothero explored Kielan-Jaworowska's career in his book, "The Story of the Dinosaurs in 25 Discoveries: Amazing Fossils and the People Who Found Them."

"She [Kielan-Jaworowska] took advantage of the fact that, although Outer Mongolia was under Soviet domination and closed to western scientists, Polish scientists could get permission and funding," Prothero says via email.

Kielan-Jaworowska became the Institute of Paleobiology's director in 1961, the year after Kozłowski retired.

These two scientists weren't done collaborating, however. Kozłowski hatched the idea of organizing a series of collaborative Polish-Mongolian paleontology expeditions through the Gobi. At his suggestion, Kielan-Jaworowska wrote a detailed proposal for three such journeys.

Both the Polish and Mongolian Academies of Science signed off on the project. Kielan-Jaworowska was chosen to be the initiative's lead scientist and its chief organizer.

Annalisa Berta is a paleontologist at San Diego State University who specializes in whale evolution. She also co-wrote the book "Rebels, Scholars, Explorers: Women in Vertebrate Paleontology" with Susan Turner.

As Berta says via email, these Gobi Desert adventures made Kielan-Jaworowska "the first woman to lead a dinosaur excavation expedition."

There were eight Polish-Mongolian expeditions in total; Kielan-Jaworowska led seven of them.

Besides Deinocheirus, Prothero says the participants unearthed "lots of tyrannosaurs called Tarbosaurus. They found huge sauropods, and many different kinds of 'bone headed' dinosaurs, or pachycephalosaurs... a bunch of primitive horned dinosaurs (Ceratopsia), and lots of ostrich dinosaurs (ornithomimids), including the famous Gallimimus from Jurassic Park. The list goes on and on." Her team shipped back at least 20 tons of fossils to Poland in 1965 alone.

Two particular dinosaurs stood out. In 1971, an expedition member by the name of Andrzej Sulimski noticed a beautiful Velociraptor skeleton. As the group dug it up, a second tail appeared. It turned out this raptor's fossilized body was intertwined with that of a plant-eating Protoceratops.

Now internationally famous, those "fighting dinosaurs" are housed at a museum in Ulaanbaatar, Mongolia, the nation's capital.

Even the best-planned journeys carry unexpected risks. During the last of the Polish-Mongolian expeditions, Kielan-Jaworowska ruptured her left eardrum and went home to Poland on the advice of a local doctor. Three weeks later, she flew back to the Gobi.

"As fossils from the expeditions came pouring in, she navigated Cold War roadblocks to establish ties with leading Western scholars, notably those in Britain, France and the United States," Berta says of Kielan-Jaworowska. "She built an impressive science network from her hub in Warsaw that extended throughout the world."

Although Kielan-Jaworowska began her career as an invertebrate specialist, her attention later shifted to prehistoric mammals.

"Before her work, most Cretaceous mammals were only known from a few jaws and some teeth," explains Prothero. "She found dozens of complete skulls and skeletons of nearly all the major groups of mammals that were around in the Late Cretaceous."

Beyond that, Kielan-Jaworowska changed the way scientists view some important lineages. Deltatheridium — a rat-sized mammal that coexisted with Velociraptor — was originally considered a placental mammal. But newer specimens Kielan-Jaworowska and her teams brought to light indicated the creature was more akin to marsupials.

Kielan-Jaworowska died in Warsaw March 13, 2015, just a few weeks shy of her 90th birthday. Glowing obituaries appeared in the journals "Nature" and "Acta Palaeontologica Polinica," with both publications calling her "a peerless role model."

"She set in motion a remarkable new age of exploration and discovery," Berta says. If there are any budding young dinosaur enthusiasts in your life, you'd do well to tell them her story.

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