Current Events > When did scientists discover dinosaurs lived millions of years ago?

(+) Yeah! (+)

Not the discovery of fossils themselves or the classification of the dinosaurs species, but the fact that they lived millions of years ago? IIRC scientists (western) still belived the earth was 6,000 years old.

I'm guessing it has something to do with the calcification of the bones themselves and the addition of calculating the different time periods from the dirt, rock, etc.

For some reason Da Vinci came to mind

About the same time I would imagine, dont they do carbon dating on the fossils?

Late in the 19th century scientists like Henry Becquerel and Marie Curie studied and described radioactivity and radioactive materials. In the early 20th century, a dude named Ernest Rutherford figured you could use the fact that radioactive materials decay at a predictable rate to determine how long ago something like a rock formation had formed, a technique known as radiometric dating.

So, scientists could determine how long ago a rock formation containing dinosaur fossils had been formed by how much of certain radioisotopes remained in the rock.

Press material for the 1925 dinosaur movie The Lost World claimed that dinosaurs lived approximately one million years ago. It's just kinda funny how much they lowballed that with regards to what we now know.

"That was a good estimate. They indeed lived OVER a million years ago. We're just gonna need to add another sixty four million to that estimate."

David1988 posted...

About the same time I would imagine, dont they do carbon dating on the fossils?

Carbon dating only goes back about 50k years.

Modern Paleontology and Geology are relatively new disciplines.

Most of the Rocks in my era actually too old to have fossils. By Billions of years.

Millions of years ago.

Only religious people still think the earth is only 6000 years old. And that thought is based on the Bibles long list of who father'd who, all the way back to Adam and Eve.

1907 is when half life was formulated. Because things decay at an extremely predictable rate, we can tell how old something is by how much carbon is in the bones of it's fossils.

So sometime after 1907 is when we would've figured out dinosaurs were that old.

1 million years honestly isn't a bad guess for 1925 levels of knowledge.

The earth being 6000 thing has always been a fringe belief, even among Christians. It's also a much more recent thing than Christianity itself.

But yeah, by the 1800s gelogic time scales were starting to be discovered, along with the discovery and taxonomy of various dinosaurs, with the Mesozoic, and Triassic, Jurassic etc being determined around 1840. Around then most estimates for the age of the earth were about 10 - 100 million years old, so dinosaur timescales were kinda just guesses.

As mentioned above, radioactivity was discovered in 1896, and the concept of half life in 1907. By the mid 1910s the determined age of the Earth had jumped to be at least 1.5 billion, and refined to 4.5 billion by the 1950s, with more accurate dinosaur timescales determined too.

This is actually a cool book.
I got it when it came out.
It's well written and explains a lot.

But also...a book buy its cover...The paper cover actually unfolds into the map.
That's not why I bought it, but it's damn cool!