Is it a theory or hypothesis that petroleum comes from dinosaurs and ancient plants?

It’s largely false.

Petroleum comes mostly from ancient plankton.

And that’‘s not a “theory,” because in science a theory is proven idea that ties together a large number of facts and observations. “Petroleum comes from ancient plankton” is just a simple fact.

As for tests, obviously we cannot run a multi-million year experiment to determine what happens to compressed plankton. There are however signature chemical traces that indicate oil comes largely from single-celled water-dwelling organisms. We know how the molecules that make up these organisms’ bodies decompose and become compress.

Yes, petroleum ‘came from’ biomass.

It has been accepted as fact that petroleum had biological origins, As @Qingu said. it comes from plant and animal plankton:

“modern research has traced its origin to the lipids (oils) of planktonic (free floating) plants and animals which live in brackish water such as blue-green algaes and foraminifera”

SJSU

@syz – nice site. So we should not expect the petroleum reserves to refill themselves any time soon. Drill, baby, drill never made sense to me. It is just using up resources for short term gain.

@Qingu not to be argumentative but is it a fact or is it accepted as fact?

There is a well accepted Theory of the Biological Origin of Petroleum. Use of it has predicted numerous sources of petroleum over the last century or more. There was a hypothesis of Abiogenic Petroleum Origin that was circulated in the 19th century, but after failing to predict the location of a single oil field, it was abandoned.

Science doesn’t deal in facts. It deals in probabilities. A theory in scientific jargon is not the same thing as a gut feeling or a hunch. Those are called hypotheses. An hypothesis only graduates to the level of theory after it predicts future observations, and a scientist runs experiments to confirm that those predictions are exactly what we observe. It then gets published in a peer reviewed journal and other scientists all over the world think about what “should” be observable of the hypothesis is true. They conduct experiments of their own trying to disprove it. Only if it proves predictive of actual observations in all cases does it graduate to the level of Theory. At that point it is probably that it is true.

But scientists recognize that future revelations may require that it be adjusted. Newton’s theory of gravity, for instance, was eventually proven to be ever so slightly wrong in certain very unusual circumstances. Einstein’s Theory of Relativity forced scientists to modify their understanding of gravity just a bit. But I know of not a single instance where an established theory had to be completely discarded due to further study. Not yet, anyway.

@rojo, what’s the difference in your mind, exactly?

@ETpro I appreciate the clarification.

@Qingu In my mind, a fact has been tested, proven, re-tested and re-proven. Something that is accepted as fact has not or is not absolutely provable but, given the resources we have at our disposal and the data generated it is our best guess until something better comes along.

Do you believe it’s a fact that Neptune revolves around the sun? We’ve never directly observed the whole revolution.

@Qingu That’s a prefect example of the difference between the layman’s understanding of “theory” and “fact” and how a true scientists views these concepts. Science would say that given our understanding of gravity and relativity, it is highly probable that Neptune revolves around the Sun, but we have never fully observed this to be the case.

Pft. I think if you asked a thousand astrophysicists, 999 of them would say it’s a “fact” that Neptune revolves around the sun.

And the other one would be a damn pedant.

@Qingu Then why did you bring it up? To “be a damn pedant”? :-)

‘Cuz rojo was being a pedant. :)

@Qingu Ha. I guess that makes us all club members. :-)