Have plants evolved? When did plant life first exist? Was it in the oceans that it started? What came first, the seed or the plant?

Have plants evolved?

Yes, plants have evolved; plants and all other life forms on Earth (including humans) continue to evolve.

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When did plant life first exist?

That depends on how you define “plant” (i.e., which definition of "plant" you agree with).

Most biologists say that the first land plants appeared on Earth between 430 to 510 million years ago.

Land plants evolved from a type of green algae.

Some biologists think that green algae should be classified as plants, in Kingdom Plantae.

Other biologists think that green algae belong in Kingdom Protista.

Still other biologists think that green algae belong in their very own separate Kingdom.

(All of these biologists can back their arguments up with solid evidence).

If you agree that green algae are plants, then “plants” (i.e., green algae) appeared on Earth 750 million years ago.

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Blue-green algae are another group of organisms that are difficult to classify. They are also called cyanobacteria. They used to be in Kingdom Protista, but now, they’re classified as bacteria in Kingdom Monera.

Bluegreen algae (aka cyanbacteria) were one of the first organisms to evolve the ability to photosynthesize.

The first photosynthetic bacteria appeared 3.4 billion years ago.

The first bluegreen algae (aka cyanobacteria) appeared 2.7 billion years ago.

Bluegreen algae (aka cyanbacteria) existed before green algae. Bluegreen algae didn’t evolve into green algae; Green algae were formed when a bluegreen alga became part of a brown alga.

The first brown algae appeared 1.2 billion years ago.

The first green algae appeared 750 million years ago.

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Was it in the oceans that it started?

The evolution of plants most likely occurred in fresh water, then moved into the oceans, and finally onto dry land..

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What came first, the seed or the plant?

Plants existed long before some of them evolved the ability to form seeds.

The now extinct fern, Elkinsia polymorpha evolved about 400 million years ago and is considered the earliest seed plant known to date. Their seeds were not formed in flowers.

The first angiosperms (flowering plants) likely evolved from one of gymnosperms, like ginkgo, or conifers (e.g., pines or firs).

http://study.com/academy/lesson/the-evolution-of-g...

https://www.scientificamerican.com/article/timelin...