How good is the fossil record of Cycads?

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Invertebrate Paleontology and Paleobotany is a graduate level course in paleontology at Utah State University, which covers the major groups of marine invertebrates, fossil plants, and the important techniques and tools used in the field of paleontology. It covers ichnology, fossil preservation, taphonomy, ontogeny, cladistics, biostratigraphy, paleoecology, extinction and evolutionary rates, and many other tools used by professional paleontologists in the study of fossils and their importance in the field of geology. Course lectures are produced and broadcast from the Uintah Basin Campus in Vernal, Utah. If you like more information about the course and becoming a student at Utah State University check out this website: geology.usu.edu

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8 июл 2024

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@thejdmguru621 5 месяцев назад

Not to mention that Stangeria Eriopus is the only species in the genus that is still extanct today. The Cycas Genus, like you said, is wide spread and some species have even been found in the Hawaiian islands. Zamia and Ceratozamia species range in shape and size, making it one of the most diverse plant genuses with pants ranging from small bamboo-like structures to massive trees, all with variations in leaf shape, size, and colour. The Encephelartos genus is one of the only group of cycads that contain blue leafed forms. With that blue colour coming from a special powdery coating on the leaves that protects the plants from frost burn. Something to note is that some Encephelartos species are known to grow in multiple different localities. Such as Encephelartos Natalensis which is found in 5 different places, these localities have evolved based on their environment, meaning that even though they are the same species, they look very different from each other. Some have Broad leaves with many pricks on each leaf making it look more like Encephelartos Transvenosus, then there is a special locality that makes species look almost indistinguishable from Encephelartos Woodii, which is not surprising given how closely related the two species are. On another note, I have noticed that the Encephelartos Genus, Dioon Genus and Macrozamia might all come from the same ancestor judging by the leaf structure on some of the plants. Great video

@krisinsaigon 8 лет назад

really enjoying these lectures so far- this one especially. I live in HCMC, Vietnam, and we have cycads growing across the city as ornamental plants and i have wondered about them before, when i first noticed they had strange pine cones

@BenjaminBurgerScience 8 лет назад

+kris wilkinson Cycads are really interesting plants. When you start learning about the fossil record you suddenly realize that you are surrounded by plants that span many geologic periods. New plants are discovered every year, and especially in places like Vietnam.

@krisinsaigon 8 лет назад

+Benjamin Burger thanks for replying. Yes, it's awe inspiring to think these plants have been around 100's of millions of years. I just went into city centre to buy groceries, and there is a line of Cycads along the riverfront. I looked up and could could clearly see their "pine cones", and thanks to you I know what they are know.

@wcdeich4 5 лет назад

Yes, Cycads are really fascinating. I even grow them in my garden in Florida. But something is strange about them. For a plant that has survived for millions of years, since before the dinosaurs - you would think they would be super tough & they must have evolved solutions to most of life's problems in order to have lived this long. But no. They're highly susceptible to fungus. The seeds have a low viability rate. When people break off the asexual buds or "pups" to start a new plant that way, you have to thru a long complicated process to get them to form a separate plant. Even then only about half survive......... it is really amazing plants with so many specific needs & vulnerabilities have survived for so many millions of years...... Then again, maybe they have less fungus & pollinating beetles in their home range so they're more hardy there.