Plant Evolutions

Angiosperms

Cretaceous

Angiosperms

Angiosperms began sprouting around 145 million years ago and featured over 235,000 new speices. During this time, there was an increase in the symbiotic relationship between these plants and the insects (Univ. of Waikato, 2022). They inhabit nearly every location on Earth except extreme climates. Their rapid growth in evolution is accounted towards smaller cells in result the plants could take more carbon dioxide and increase the number of pores they produce (Chrissy Sexton, 2018).

Gymnosperms

Mesozoic

Gynosperms

Gymnosperms are vascular plants that reproduce by exposed seeds. They first appeared in the late Carboniferous and were located in all locations except Antarctica (Britannica, 2008). What allowed them to become the dominant species were it's protective layers that allowed them to reproduce and grow. As well as created sperm like pollen that could be carried in the wind to a female to sexually reproduce (Biology ll, 2022).

Ferns

Ferns are predated as early as the Carboniferous period. Prehistoric ferns had various growth tatics from climbing to epiphytic forms (Waterloo, 2022). Ferns predominantly inhabited warm, damp environments. They have both male and female sex organs to either self fertilize or release spores. Ferns were also a food source for herbivores (Britannica, 1996).

Ferns

Ginkgo

Ginkgo are large trees with fan-shaped leaves. It's first appearance is dated during the Permian and it's modern species sprouting in Middle Jurassic. They grow in damp, warm climates preferably in direct sunlit areas (Wikipedia, 2022). Most of Ginkgos trees are located in Eastern and Central China. It's modern species can be used for medicinal purposes such as improve blood circulation and vision (Crane, 2018).

Ginkgo

Sphenopsids

Sphenopsids are vascular plants that are jointed ribbed stems (Webster, 2022). They were found in damp environments such as swamps. They used to grow as tall as thirty meters long but modern speices are only about ten feet in height. There are now only about thirty living specie types of this plant around the world (Wisconsin, 2022).

Lycopods

Lycopods have unique leaves called microphylls that have veins running through it. The tree lacks seeds, fruits, flowers, and wood. They are found in every environment except etreme cold locations (Biology, 2022). There oldest known form is during the Silurian Period. Before modern species they were able to grow 100 feet tall (IOP, 2022).

Lycopods

Asteroxylon

Asteroxylon were vascular plants with branches steming 12 mm long. They orginated around the early Devonian era but are now currently extinct. Asteroxylon would often be found in hot spring ecosystems (Hetherington, 2021).

Asteroxylon

Cycads

Cycads are palmlike, woody vascular plants. They produce pollen that is carried by insects or the wind to fertilize other cycads. They prefer warm, damp environments with partial sunlight but some variations have adpated to dry environments. They first appeared during the Permian period and Mesozoic. They are large slow growing plants (Britannica, 2022).

Cycads

Conifers

Conifers are needle-shaped evergreen leaves and seeds attached to the tree. They are mostly found in warmer arease and tropical mountains. The earliest forms of Conifers date back to late Carboniferous period. They were the dominant land plants in the Mesozoic era. Like many other plants they have spores used to sxually reproduce with other conifers (Wikipedia, 2022).

Conifers

Citation

“Plant and Animal Evolution.” Plant Evolution, https://sci.waikato.ac.nz/evolution/plantEvolution.shtml.

Sexton, Chrissy. “How Flowering Plants Became so Dominant on Earth.” Earth.com, 17 Jan. 2018, https://www.earth.com/news/flowering-plants-dominant-earth/.

“Gymnosperm: Additional Information.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 18 Apr. 2008, https://www.britannica.com/plant/gymnosperm/additional-info#history.

College, Northern Virginia Community. “Biology II.” Evolution of Seed Plants | Biology II, https://courses.lumenlearning.com/suny-biology2xmaster/chapter/evolution-of-seed-plants/.

“Fern Fossils.” Earth Sciences Museum, 19 Dec. 2013, https://uwaterloo.ca/earth-sciences-museum/resources/fern-fossils#:~:text=Ferns%20are%20a%20very%20ancient,to%20several%20modern%20families%20appeared.

“Ferns and Lycophytes | Basic Biology.” LYCOPHYTES, https://basicbiology.net/plants/ferns-lycophytes.

Citation