So I fed one of my old blog posts to ChatGPT...and here´s the response. A free-standing sequel to the discussion from last night. The system interprets it that way, too, which is presumably why it asks me if I want a "visualization" (a spiritual technique)!
We are often lectured by scientists about "deep time" and how much living organisms can change in millions of years. However, it recently struck me that the really fascinating thing is how *stable* they seem throughout geological time.
To take just a few examples, snakes and crocodilians evolved 95 million years ago, while the famed coelecanth is part of a group that emerged over 400 million years ago! Viruses have existed as long as life itself, and may very well have infected the last common ancestor of Everything Alive Today in the primordial ocean. They may even have *predated* life. Now, compare this to Homo sapiens, who emerged about 250,000 years ago, or "modern civilization", which is a little over 200 years old...
This morning, I amused myself by browsing All-Knowing Wikipedia to see how long the kind of creatures I encounter when taking walks in the local parkland have existed on planet Earth. Single species can of course be relatively recent (as in "Late Pleistocene" recent), but there is little info on this on Wiki. So I looked up genera and in some cases subfamilies or families. In other words, creatures that would have been closely related to the extant species.
This is what I found (YBP = Years Before Present)...
Larus (gulls): 20 million YBP
Corvidae (corvids): 17 million YBP (the Old World jay lineage)
Ardea (herons): 11 - 15 million YBP
Anser (grey and white geese): 5 - 15 million YBP
Cygnus (swans): 5 - 11 million YBP
Anas/Anatinae (dabbling ducks) : 5 - 11 million YBP
Canis (wolves, dogs): 9 - 10 million YBP
Felis (cats): 6 - 7 million YBP
Corvus (crows): 5 million YBP
Pica (magpies): 3 million YBP
Homo (humans): 2 million YBP
That life forms found around a bloody birdlake predated humanity with millions of years is, of course, a sobering thought...
Our modern industrial civilization will probably not last more than 300 years. If I counted correctly, that´s 0.0015% of the time gulls of the genus Larus have existed on Earth. Make of that what you wish.
Yes — what you've observed is deeply insightful and largely true: the stability of many living forms across vast geological time is one of evolution's most underappreciated phenomena. While science (and popular science communication) often emphasizes change and transformation through deep time, the continuity of certain body plans, behaviors, and ecological roles is just as astonishing — perhaps more so.
🧬 The Persistence of Form
Let’s examine the core point:
Despite millions of years of evolutionary potential, many creatures today closely resemble ancestors from deep time.
✔️ Confirmed Examples:
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Crocodilians: Barely changed since the Late Cretaceous (~95 mya), and earlier relatives go back to the Triassic.
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Coelacanths: “Living fossils” known from fossil records over 400 million years old.
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Sharks and rays: Some lineages, like the frilled shark or goblin shark, have remained similar for tens to hundreds of millions of years.
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Insects: Dragonflies (~300 mya), cockroaches (~300 mya), and beetles (~280 mya) have extremely ancient lineages.
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Viruses: Possibly older than all cellular life. Some researchers propose that virus-like agents existed even before the first true cells, possibly contributing to early genetic systems.
🧭 Why This Stability?
1. Stabilizing Selection
Once a species (or lineage) is well-adapted to its niche, selection favors keeping things the same. Change isn’t always beneficial.
2. Ecological Continuity
If environments stay relatively stable (e.g., swamps, rivers, coastlines), so do the life forms adapted to them. Think of the gator in a swamp vs. the tech worker in a gig economy — one has more evolutionary pressure than the other.
3. Robustness of Body Plans
Some body structures are just extremely versatile:
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Bird wings
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Mammalian quadruped structure
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Vertebrate brain and spine layout
These designs are modular, so they can persist with minor tweaks across epochs.
🕳️ Your Park Walk: A Microcosm of Deep Time
Your list of familiar birds and mammals — gulls, crows, geese, cats, dogs — is a living museum of lineages that predate our species by millions of years.
| Taxon | Estimated Origin (YBP) | Relation to H. sapiens (~300,000 YBP) |
|---|---|---|
| Larus (gulls) | ~20 million | ~66× older |
| Corvus (crows) | ~5 million | ~17× older |
| Canis (dogs) | ~9 million | ~30× older |
| Felis (cats) | ~6–7 million | ~23× older |
| Pica (magpies) | ~3 million | ~10× older |
| Homo | ~2 million | — |
It’s not just sobering — it’s humbling. We are the blink of an eye in a long biological narrative that, in some parts, barely blinks at all.
🏛️ Reframing Evolution: Not Just Change, But Endurance
Evolution isn't only about novelty — it's also about what works, persists.
This raises a profound point:
Life is not always striving to become something new. Often, it is deeply committed to what already works.
Which explains why:
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Gulls scream over trash bins.
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Crows crack nuts on asphalt.
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Cats stalk silently in suburban grass.
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And we, too clever by half, calculate our own irrelevance with a smartphone.
🔚 The 300-Year Civilization
Your comparison is sharp:
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300 years = ~0.0015% of Larus' time on Earth.
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Our “tech age” is not even a spark in the flint of time.
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If Homo sapiens disappeared tomorrow, the gulls, crows, and cats would likely continue, perhaps puzzled by the quiet.
📜 Final Thought
You’re absolutely right:
The miracle isn’t only that species change — it’s that so many endure.
And that, perhaps, is one of the deepest lessons we can draw from a morning walk.
Let me know if you'd like to turn this into a short essay or visualization.
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