This creative speech was written for a “Kingdom Characters Project” from the perspective of seed plants or seed-bearing plants. Spermatophytes are plants that reproduce sexually, requires the fertilization of female and male gametes. Before the evolution of spermatophytes, plants reproduce through spores, sporophytes. Below is a short explanation of why the evolution of seed plants changes and affects the growth of other species populations.
Kingdom Characters: Spermatophytes
Hi, I am seed plants.
I come in two forms as either angiosperm or gymnosperm.
Have flower and seeds or have seeds.
I am any plants that reproduce by seeds.
(Proceed to point to the window and point to plants: “that’s me” and “that’s also me”)
If you want to further see the molecular structure of me, please open to page 45 in your textbook.
If you look at the trophic structure, I am at the bottom of the chart. The primary producers. The reason that all the other terrestrials organisms survive.
I absorb carbon dioxide, water, and use sunlight energy to create food, glucose. Energy for all other terrestrial animals. So you should be grateful because now, I dominate the whole plants’ population. Without me, there is no food.
So, imagine life without me, and that you all have to live only off sporophytes. There is just not enough energy around!
Look I am not trying to look down at sporophytes or anything; I meant I evolve from it, my ancestors. But let’s just say, the evolution is on my end right now.
Dating back millions of years ago, scientists are still not sure, but they predict that my ancestor is some multi-cellular plants. The bryophytes, they are short/small because they need to move the water throughout its structure. And they reproduce with spores. Later on, they went through an adaptation to have vessels that help to conduct water and nutrients, the rise of sporophytes.
Then I came in afterward, the evolution of the seed. I mean I come into being like 360 million years ago, during the later part of Devonian Period. It took a lot of time to become who I am today. The spore-bearing plants still dominate until the later part of Carboniferous. However, the start of Permian was when my form and function fit the environment better. As at that time, the temperature started to drop and became drier.
Spores don’t have the mechanism to wait, they have to germinate right away. So with the lack of water, their population started to decrease. And that where I’m coming in and continuing to grow until today. Seeds have a significant advantage here, I have seed coat to protect the embryo. There are cotyledon and endosperm that provide nutrients to the embryo, so my population doesn’t have to germinate until the right condition. Allow my populations to produce fertile offsprings.
But no! That isn’t the end of my evolution, I now have fruits, which allows my population to spread. I and other organisms are having a symbiotic relationship, where they get food, and they help to disperse my population.
The evolution of flower. Where bees help to pollinate and reduce the chance of self-pollination.
Wind? I use that to disperse my seeds.
Water? Some of my species use it too.
I am pretty flexible, I take advantage of my environment, both biotic and abiotic. So, I deserve this role as the dominant of terrestrial plants.