Join me on my 'plant-astic' journey

Take a look outside at the lush green mountain ranges that surround you. Take a leisurely hike through a nearby nature track. Perhaps take a walk through your local botanic garden, or even your own garden, and count the number of different types of trees, plants and flowers you see. Chances are, there will be more plants than you would want to, or could care to count. Close your eyes and take a deep breath, fill your lungs with the oxygen that plants produce through photosynthesis.


When the Earth formed approximately 4.5 billion years ago, our planet was lifeless and vastly different from the unique and diversified ‘David Attenborough style’ planet we see today. The origin of plant life remained stagnant for several billions of years until a photosynthetic algae, Cyanobacteria, changed the surface of the Earth 1.2 billion years ago and paved the way for other terrestrial plant forms to flourish around 500 million years ago.


It is estimated that there are now more than 290,000 different plant species which cover the majority of the land mass of the Earth, excluding polar and desert regions. Considering the Earth is covered by more than 70% water; that is quite an extraordinary range of diversity which originated from our humble friend Cyanobacteria.


My aim over the next several posts is to take you on a journey from the Charophytes of the Paleozoic era through to the Angiosperms of the Cenozoic era, and look at the origins of these terrestrial plants and how they evolved into the complex and wonderful plant life we see and enjoy today.


References:

Reece, J.B. & Campbell, N.A. 2012, Campbell biology, 9th (Australian version) edn, Pearson Australia, Frenchs Forest, N.S.W.

Comments

  1. Tasmin10 March 2018 at 16:15

    I really nice introduction. I look forward to reading your next post!

    ReplyDelete

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