It made me very happy at the end of Episodes 2 to 5 of the new BBC series ‘Evolution’ when the words “The Evidence” appeared as a title on the screen. As a scientist, this is what I had been waiting for. These sections obviously contain some of the strongest scientific content of the series. They show several scientists, mainly talking about transitional fossils. Despite this, there is still a tendency to assume, rather than defend, evolution. The fossils tend to be presented as filling in details of an evolutionary story that we know must have happened, rather than explicitly as evidence for evolution per se. The emphasis is overwhelmingly on pattern rather than process. It does not seem to have crossed the mind of the BBC team that some viewers might have their doubts about the validity of evolution as a complete explanation for how we got here, and might want evidence for that, rather than evidence for one particular pathway over another.
“The Evidence” section at the end of Episode 2 tackles the question “How do we know birds are living dinosaurs?” Defined narrowly, this is a systematic question relating to the pattern of life. We are told the “first clue” was the discovery of Archaeopteryx which is “an icon of evolution”. Packham tells us: “It wasn’t just a bird, it was also a dinosaur. Other discoveries followed that left no room for doubt”. We are shown fossils of Archaeonithura and Anchiornis, and scientists explain the morphological similarities between dinosaurs and birds, such as a wishbone, beak, warm bloodedness and feathers. The implication is that these similarities are evidence for evolution, but this is assumed rather than stated. The evidence tends to be described as simply fleshing out the details of the dinosaur-bird evolutionary story, rather than as providing evidence for evolution itself: “We can see the evolutionary origins of many bird traits among their ancestors the dinosaurs”.
We are told that “one key question remains” and this is why birds survived when their dinosaur relatives went extinct. We are shown the fossil of a chicken-like bird that co-existed with the dinosaurs just before they went extinct, and we are told that birds like this probably survived because they were generalist feeders. Ostriches today show us that “the story of dinosaur evolution is not over”.
At the end of Episode 3 (The Bat) the section on “The Evidence” is not about evidence for evolution, it is about the evidence that the BBC animators used to reconstruct what Metaspriggina fossils from the Burgess Shale may have looked like when alive. This is followed simply by a statement:
It is incredible to think that these tiny little forms are the ancestors of such diversity of life today”
If it is “incredible” maybe the focus should have been on evidence for the evolutionary process, rather than evidence about the realism of the animation?
“The Evidence” section for Episode 4 (The Dolphin) seeks to tackle the question “How do we know that the ancestors of dolphins once walked on land?” We are shown a fossil of Indohyus, which looks like a land mammal but has a thickened region of the ear bone that today is only found in whales and dolphins. A scientist says “That’s really the smoking gun that Indohyus is closely related to whales and dolphins.” Chris Packham immediately adds “Evidence that it was already adapting to a life underwater, completing the remarkable story of how land mammals evolved into marine cetaceans.” Quite where the word “complete” came from I am not sure.
At the end of Episode 5, (The Hores) the evidence section starts with a curator from the Natural History Museum showing us a cast of a fossil of Tiktaalik. We are informed:
It looks like a cross between a fish and an amphibian, and that’s because that’s exactly what it is.
Tiktaalik was really this kind of unique snapshot in evolutionary time at this key moment for the water-to-land transition.
So it’s a perfect example of a transitional fossil.
That is quite a strong claim, given that some scientists believe that the water-to-land transition happened several million years before the Tiktaalik fossil was formed.
But leaving that aside, it struck me as surprising that, even in this final section on “The Evidence”, evolution continues to be treated as a fact to be illustrated, rather than a hypothesis to be tested against evidence. One scientist says:
Transitional fossils…play the really important role of filling those gaps between morphologies that we kind of know are there, but we don’t really know exactly what they might have looked like.
So evolution is simply assumed as a known, and transitional fossils, rather than helping convince us of its truth, just help us know the forms that it went through.
The section is a little ambiguous about how complete the fossil record is from an evolutionary perspective. On the one scientist tells us:
If we think about a book, you have lots of different pages that tell us the story from start to finish. However, with evolution and fossils, some of those pages are missing.
Making it sound as if there are just “some” gaps, but the story is pretty complete. On the other hand, soon after we are told by another scientist:
Transitional fossils are incredibly rare
So are some pages missing or are the vast majority? The viewer is left uncertain. If transitional fossils are rare, does that mean that evidence for evolution is rare? Or is there also other evidence? Images labelled as “Archeopteryx: Dinosaur-Bird”, “Ambulocetus: Walking Whale” and “Metaspriggina: Primitive Fish” flash across the screen, followed by a bewildering array other fossils, and that is it.
The take home message, from both the brevity and content of the sections, seems to be that evidence doesn’t matter very much, and evolution is simply a fact.
The take home message…seems to be that evidence doesn’t matter very much
To my mind, that is not a good way to teach science. In addition, it makes no effort to understand how the significant percentage of the UK population who doubt aspects of evolution might think. If some viewers aren’t convinced that evolution is how we got here based on the similarities of life in the living world, will showing them a few more similarities in extinct life really make much difference?
In the final part of “The Evidence” section in Episode 5 we are told this about the processes used by the animation team to illustrate evoluton:
After consulting scientists to accurately model the key evolutionary changes, they used generative AI software to create hundreds of variations representing countless generations. And by hand selecting and merging the best results with their original animations, they were able to condense millions of years of evolution into a matter of seconds.
Clearly, this hand-curated output of AI is not evidence for mindless, unguided evolution. If it is evidence for anything (and I am not sure it is) it is evidence that we need to use complex software and human intervention to be able to model evolutionary processes. What does that imply about evolutionary processes themselves?
We are then shown various scientists looking at the animation that the BBC has produced to try to illustrate evolution, and we hear them exclaim:
– Look at that!
– There’s bones inside!
– No way.
– In reality, this would take millions of years.
– This is a fantastic way to illustrate the evolution of form.
– This is basically how I imagine it playing out in my head.
This closing scene is a remarkable contrast to Chris Packham’s opening word to the series:
It’s easy to imagine that all of this is, like, somehow preordained, that it’s been made, a world of balance and purpose. But the truth…The truth is much wilder.
These opening words denied that there could have been any intelligence guiding evolution, and that to think so is a figment of the imagination. Yet this (almost) final closing scene is of animators using human and artificial intelligence to try to recapitulate evolution, with a scientist watching the output and saying “this is basically how I imagine it”.
Ironically, we seem to have come a full circle.
Featured image: Still from BBC Evolution series 2026