In Our Time — Feathered Dinosaurs

Host: Melvyn Bragg
Guests: Mike Benton, Steve Brusatte, Maria McNamara
Originally Aired: December 11, 2025

Episode Overview

This special archive episode of “In Our Time” explores the fascinating topic of feathered dinosaurs, chronicling the transformation over recent decades in how scientists and the public have come to understand dinosaurs—not as lumbering, cold-blooded reptiles, but as dynamic, often feathered ancestors of modern birds. Melvyn Bragg is joined by vertebrate paleontology experts Mike Benton, Steve Brusatte, and Maria McNamara, who discuss the history of dinosaur research, the revolutionary fossil evidence from China, what feathers tell us about dinosaur biology and evolution, and the ongoing mysteries in the field.

Key Discussion Points and Insights

1. Changing Views on Dinosaurs

• For much of the 20th century, dinosaurs were depicted as slow, heavy, gray-skinned lizards. This image was rooted in early discoveries, pop culture, and the sheer “otherness” of their fossils ([03:33] Mike Benton).
  • Quote:
    “We still commonly use the word dinosaur to mean a sort of failure or something that's lumbering and hopeless.” — Mike Benton [03:33]
• The scientific view changed radically in the late 20th century as new fossil discoveries pointed toward a more active, bird-like image.

2. Historical Hints: Darwin, Huxley, and Early Bird Fossils

• Thomas Huxley recognized as early as the 1860s that birds and small theropod dinosaurs were closely related, based on fossils like Archaeopteryx ([05:52] Mike Benton).
  • Quote:
    “Apart from its feathers, Archaeopteryx had the skeleton of a little dinosaur.” — Mike Benton [05:52]
• Despite Huxley’s insights, the view of dinosaurs as reptilian “monsters” persisted for another century.

3. The Dinosaur Family Tree and the Rise of Birds

• Dinosaurs appeared about 230 million years ago, diversified slowly, and dominated until an asteroid strike wiped out most species 66 million years ago—except the lineage that led to modern birds ([08:14] Steve Brusatte).
• Three key dinosaur groups:
  • Sauropods (long-necks, e.g., Brontosaurus)
  • Ornithischians (beaked plant-eaters, e.g., Triceratops)
  • Theropods (meat-eaters; birds evolved from these) ([10:58] Steve Brusatte)

4. What Are Feathers?

• Maria McNamara explains feather development in modern birds, from simple skin outgrowths to the highly branched structures seen today ([12:21] Maria McNamara).

  • Quote: “They're actually the most complex structures derived from the skin in vertebrates, animals with backbones.” — Maria McNamara [12:21]

• Fossil evidence reveals a range of feather complexity—from simple filaments to fully modern feathers—trackable both in embryos and across dinosaur groups ([14:17] Maria McNamara).

5. The Fossil Revolution: China’s Extraordinary Discoveries

• The mid-1990s brought game-changing discoveries from northeast China (Jehol Biota and Daohugou Biota), where thousands of exquisitely preserved feathered dinosaur fossils were found ([15:25] Maria McNamara; [16:37] Maria McNamara).
  • Notable moment:
    “Sinosauropteryx...absolutely electrified the world of paleontology because this dinosaur preserved feathers.” — Maria McNamara [15:25]
• The exceptional preservation is attributed to fine lake sediments and volcanic ash, which sealed in details of feathers and even colors ([18:16] Mike Benton).

6. Vindication of Theories: John Ostrom and Deinonychus

• In the 1960s, John Ostrom’s studies of Deinonychus suggested a nimble, feathered, bird-like dinosaur, prefiguring the feathered fossils found decades later ([19:10] Mike Benton).

7. How Widespread Were Feathers Among Dinosaurs?

• Most feathered fossils belong to theropods, but some ornithischians (plant-eaters) also had feather-like filaments. This implies that feathers (or proto-feathers) likely originated at or near the base of the dinosaur family tree ([23:44] Steve Brusatte).
  • Quote: “To me that indicates...probably feathers go all the way back to the base of dinosaurs. Probably all dinosaurs had some type of feather.” — Steve Brusatte [23:44]

8. Evolutionary Function of Feathers

• Early feathers likely evolved not for flight, but for insulation or display (as in striped tails—possibly for courtship or rivalry displays) ([33:58] Steve Brusatte; [38:41] Mike Benton).
  • Quote:
    “Feathers first evolved for something else, probably for insulation...then that one group of small meat-eating dinosaurs changed their feathers, turned their feathers into things that could form wings...even wings did not evolve for flight...maybe they evolved as some kind of display billboard on the arms.” — Steve Brusatte [33:58]

9. Dinosaur Coloration: Unlocking Prehistoric Palettes

• Modern techniques can identify pigment granules (melanosomes) in fossil feathers, allowing researchers to reconstruct color patterns (e.g., Sinosauropteryx was a ginger-colored dinosaur with a striped tail) ([35:35] Maria McNamara).
  • Quote:
    “Sinoceropteryx...those primitive hair like structures, they contain melanosomes...those melanosomes...are shaped like little balls. So Sinoceropteryx was a ginger dinosaur.” — Maria McNamara [36:12]

10. Mosaic Evolution and Wing Development

• The evolution of feathers and wings was not a straight line but a “mosaic,” with different body regions and types of feathers evolving at different rates in different lineages ([40:44] Maria McNamara).

11. The Bird-Dinosaur Transition: Archaeopteryx to Modern Birds

• Archaeopteryx, from 150 million years ago, represents the first “proper” bird with powered flight, but nearly all of its features are now traceable further back into its dinosaur ancestors ([42:03] Mike Benton).

12. Why Did Birds Survive and Other Dinosaurs Perish?

• The reason why some birds survived the asteroid extinction, but most dinosaur groups did not, remains a mystery ([44:47] Mike Benton).

Notable Quotes & Memorable Moments

• On the cultural image of dinosaurs:
  “People liked the idea because it was something like a fictional world. It was something like dragons and monsters and we all want to believe in those kinds of things.” — Mike Benton [04:42]

• Summing up the dinosaur-bird connection:
  “Birds come from theropod dinosaurs. They evolved from theropods the same way humans evolved from apes. So birds are theropod dinosaurs.” — Steve Brusatte [10:58]

• On the impact of modern Chinese fossils:
  “With these Chinese feathered dinosaurs, they are definitively the most important fossils that have been found, at least in my lifetime.” — Steve Brusatte [23:44]

• On science as an ongoing revolution:
  “This revolution has not ended, it is still ongoing. And who knows what the next big find is going to be, but it'll probably happen in the next few weeks.” — Steve Brusatte [44:33]

Timestamps for Key Segments

• Introduction, Change in Public Image of Dinosaurs: [01:55]–[05:35]
• Early Bird-Dinosaur Theories (Huxley, Archaeopteryx): [05:35]–[08:03]
• Dinosaur Timeframe and Clades: [08:14]–[10:58]
• Feather Structure & Evolution: [12:15]–[14:54]
• Discovery of Chinese Fossil Fields: [15:08]–[17:05]
• Exceptional Preservation & Ash Beds: [18:06]–[18:48]
• John Ostrom & Deinonychus Story: [19:10]–[20:44]
• Range of Feathered Dinosaurs: [23:44]–[25:57]
• Feather Evolution Functions: [33:58]–[35:18]
• Fossil Feather Coloration: [35:35]–[37:23]
• Maniraptorans, Display & Behavior: [38:41]–[39:21]
• Bird Survival & Dinosaur Extinction: [44:47]–[45:39]
• Remaining Mysteries & Future Challenges: [45:39]–[52:15] (includes bonus material)

Unanswered Questions and Ongoing Mysteries

• Why did only certain birds survive the mass extinction when most dinosaurs—including many other bird species—did not?
• Do any sauropods (long-necked dinosaurs) show evidence of feathers? If so, it would further confirm feathers as a deep-rooted dinosaur trait ([46:22] Maria McNamara).
• How did the flight apparatus and feather-bearing skin co-evolve for true powered flight in birds?
• What about the deepest origins—can more primitive fossils push our knowledge even further back?

Conclusion

This episode offers a sweeping yet detailed tour through the rich story of dinosaur research—from Victorian fossils and outdated lizard-like depictions, to electrifying Chinese discoveries and the realization that feathers are fundamental to dinosaur (and thus avian) evolution. Bragg’s guests distill decades of research into engaging stories and insights, reminding listeners that the dramatic “dinosaur revolution” is very much ongoing—and that open questions remain for the next generation of paleontologists.

For further study:

• Recommended reading: Works by Mike Benton and Steve Brusatte
• Next week’s topic: Picasso’s “Guernica” and the events of 1937

Summary compiled for listeners seeking a comprehensive guide to the discussions and revelations on feathered dinosaurs, including key insights, moments, and questions still facing paleontology.