All Yesterdays: imagining the lives fossils do not preserve

All Yesterdays: Unique and Speculative Views of Dinosaurs and Other Prehistoric Animals is an illustrated book about how paleontologists and artists imagine extinct life. Published in 2012, it was created by John Conway, C. M. Kösemen and Darren Naish, with skeletal drawings by Scott Hartman. Its central question is simple: how much of a living animal disappears when only its bones are likely to fossilize?

The book challenges a familiar habit in paleoart: drawing an animal as if its skin were stretched tightly over a skeleton, then treating that picture as neutral fact. Living animals have fat, folds, display structures, varied coverings and behaviours that bones may not record. The authors use carefully considered speculation to show how much remains uncertain, while making clear that a plausible image is not the same as a proven one.

Two complementary halves

The book’s first part offers unusual but intended-to-be-plausible views of extinct animals. Some images focus on body shape and soft tissue; others consider ordinary moments such as rest, feeding, display or interaction. The point is not to claim that a particular fossil animal definitely behaved in the illustrated way. Instead, the images ask whether the evidence rules the possibility out, and whether modern reconstructions have been too conservative in the details they leave blank.

The second part turns the question around. It imagines future researchers encountering the fossilized remains of animals that live today. If they had only bones, what might they miss about a rabbit, bird or other familiar creature? This reversal is effective because readers already know what those living animals look like. A fossil-only reconstruction can feel convincing and still omit features that are obvious in life.

These sections work together as an exercise in perspective. The first expands the reader’s sense of what extinct animals could have been like; the second shows how incomplete evidence can constrain even a smart reconstruction. The book does not say that every picture is equally likely. It shows that confidence should match the evidence, and that an artist can signal uncertainty rather than hide it behind a polished surface.

Evidence, possibility and imagination

The title’s invitation to imagine does not remove scientific boundaries. Bones can constrain posture and proportions. Trackways can record movement at a particular place and time. Skin impressions, feathers and other rare traces may preserve features that skeletons cannot. Comparisons with living relatives help researchers think about muscles, coverings and behaviour, but those comparisons must be used carefully: a bird or crocodilian is not a direct stand-in for every extinct animal.

Many of the book’s ideas concern things that rarely fossilize. Soft tissue decays, colour is usually difficult to recover, and short-lived behaviour almost never leaves direct evidence. That does not make every guess equally good. A reconstruction should be anatomically possible and consistent with what is known about the animal; when evidence is absent, the image should be understood as an informed possibility, not an observation.

For example, a Velociraptor is known from skeletal material that supports a feathered reconstruction, but many details of colour and display remain uncertain. A Triceratops skull and body outline constrain its form, while the precise appearance of some soft tissues and the texture of living skin are much harder to establish. The book encourages readers to keep those categories separate instead of turning artistic certainty into scientific certainty.

Why the images matter

The illustrations do more than decorate a short text. They make assumptions visible and invite comparison. A familiar posture may seem natural because viewers have seen it many times, not because the fossil record demands it. When an image proposes a different stance or a less theatrical moment, it asks the reader to examine the conventions that shaped older pictures.

The book also expands what counts as an interesting dinosaur scene. Prehistoric animals need not always be fighting, roaring or chasing prey. Like living animals, they would have spent much of their time resting, moving through a habitat, interacting with others or doing things that would not make a dramatic poster. This shift makes dinosaur reconstructions feel less like collections of monsters and more like attempts to picture real organisms.

Its influence comes from the clarity of that challenge. The authors do not replace one fixed visual formula with another. They show that a reconstruction can be vivid and still remain open to revision. That is an important standard for public-facing paleontology: readers deserve to know which details come from fossils, which are supported by analogy and which are artistic choices.

Where the book is deliberately speculative

Some images in All Yesterdays are intentionally imaginative. The authors use them to explore the range of plausible appearance and behaviour, and to reveal the role of convention. They should not be cited as evidence that a specific extinct species had a particular pattern, social ritual or soft-tissue feature. The book’s method is useful precisely because it distinguishes possibility from established fact.

This makes it different from a standard field guide or a taxonomic reference. It is not designed to summarize every group of dinosaurs, list species or provide a final reconstruction. A reader looking for identification should use a current scientific guide. Someone interested in how scientists and artists move from fossils to images will find a more direct conversation here.

The work fits naturally in our Dinosaur books collection, alongside both popular science and fiction. Readers can also use the dinosaur species catalogue to look up named animals encountered in the illustrations. The book is most rewarding when treated as a prompt for critical looking: ask what is preserved, what is inferred, and what the artist has chosen to make visible.

A concise but lasting contribution

All Yesterdays is short compared with a full scientific monograph, yet its visual argument has proved easy to discuss and remember. It invites readers to be curious without pretending that speculation has solved the unknown. That balance makes it valuable to artists, students and anyone who has wondered how confidently an image can portray an animal known mainly from fossil remains.

Its best lesson is not that every dinosaur should be drawn in an unexpected way. It is that reconstruction involves choices, and those choices should remain visible. A fossil can support a range of plausible lives; careful art can explore that range while respecting the difference between what is known and what remains open.