The Evolution of Green Algae into Land Plants

Lesson Transcript
Instructor: Christopher Muscato

Chris has a master's degree in history and teaches at the University of Northern Colorado.

All plants that grow on land are descended from green algae, which tends to grow on damp surfaces like rocks and wood exposed to the elements. Learn more about the evolution of green algae into land plants, which scientists believe began around 410 million years ago. Updated: 11/11/2021

The Evolution of Plants

This is a cabbage. And this is a pine tree. And this is a petunia. Know what they all have in common? They're all land plants, which is a term that means exactly what it implies. Land plants are those that grow on land, as opposed to those that grow in water. There are hundreds of thousands of land plants, and recently researchers have confirmed that all of these plants came from the same ancestor.

For a long time, people had observed the similarities between land plants and green algae, one of the four kinds of algae. But it wasn't until the rise of technologies that allowed for more accurate genetic mapping that we could demonstrate that all land plants did in fact evolve from green algae. So, all lands plants, from flowers to fruits to towering trees, all evolved from a slimy green cluster of microorganisms. How's that for an evolutionary success story?

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Classification of Vascular, Nonvascular, Monocot & Dicot Plants

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 00:00 The Evolution of Plants
  • 1:03 Green Algae
  • 2:25 From Green Algae to…
  • 4:23 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed

Green Algae

Well, since green algae was so important to this world, I guess we should get to know it. There are four basic types of algae, so green algae is defined by a few unique traits. All algae have some form of chlorophyll, the green pigment that lets plants absorb energy from light. But most algae only have one type of it.

Green algae has two kinds of chlorophyll, called chlorophyll a and chlorophyll b, which not only gives it that bright green color, but lets it absorb light more efficiently. Because of this, green algae is the only kind of algae to store carbohydrates as a starch, not as a lipid, which is better for long term energy without drying out the individual cells. These are the main characteristics that define green algae.

Now, within the larger group of green algae there are three types. You're got your basic unicellular algae, which form large colonies of single celled microorganisms. Then you've got your multicellular algae that only form long strands of individual cells lined end to end. Finally, you've got the charophytes, multicellular algae that form broad, thick filaments. These guys are where we start when looking at the evolution of land plants.

From Green Algae to Land Plants

Let's jump back in time a bit. We are now in the Silurian period of the Paleozoic era, roughly 410 million years ago. The four types of algae all exist, and all four are starting to move slowly from shallow water onto land. Only one will be ultimately successful. At this time, shallow freshwater pools and muddy banks are covered in large, flat mats of charophytes. These mats can exist partially out of water because they are slowly developing resistant coatings to prevent them from drying out.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it now
Create an account to start this course today
Used by over 30 million students worldwide
Create an account