Pikaia GudangMovies21 Rebahinxxi LK21

    Pikaia gracilens adalah spesies cacing bulu atau Polychaeta yang diketahui dari Batu Burgess pada kala Kambrium Tengah di British Columbia. Pikaia merupakan hewan chordata tertua yang pernah ditemukan. Enam belas spesimen diketahui dari Lapisan sedimen Phyllopoda Besar, dimana mereka terdiri dari 0.03% dari komunitas. Hewan ini mirip lancelet dan kemungkinan besar berenang seperti sidat.
    Posisi filogenetis tepatnya masih belum jelas. Afinitas yang diusulkan termasuk cephalochordata, craniata, atau chordata batang yang tidak berkerabat dekat ke garis keturunan chordata apapun yang masih hidup.


    Deskripsi



    Pikaia adalah chordata primitif yang tidak memiliki kepala yang dirumuskan dengan baik dan panjangnya kira-kira sekitar 1+1⁄2 inci (38 mm). Hewan ini sempat dikira berkerabat dekat ke nenek moyang dari semua vertebrata, karena alasan itu, fosil ini mendapat perhatian khusus di antara banyak fosil hewan yang ditemukan di Batu Burgess yang terkenal di pegunungan British Columbia, Kanada.


    Penemuan


    Fosil Pikaia pertamakali ditemukan pada 1911, oleh Charles Walcott, di dekat Puncak Pika, Pegunungan Rocky Kanada, British Columbia, dekat Batu Burgess.


    Catatan




    Referensi




    Bacaan lebih lanjut


    Bishop, A., Woolley, A. and Hamilton, W. (1999) Minerals, Rocks and Fossils. London: Phillip's
    Lacalli T. (2012) "The Middle Cambrian fossil Pikaia and the evolution of chordate swimming". EvoDevo 3: 12. DOI:10.1186/2041-9139-3-12
    Conway Morris, Simon. 1998. The Crucible of Creation: The Burgess Shale and the Rise of Animals. Oxford University Press, New York, New York.
    Gould, Stephen Jay. 1989. Wonderful Life: The Burgess Shale and the Nature of History. W. W. Norton, New York, NY.
    Norman, D. (1994) Prehistoric Life: the Rise of the Vertebrates, London: Boxtree
    Sheldon, P., Palmer D., Spicer, B. (2001). Fossils and the History of Life. Aberystwyth: Cambrian Printers/The Open University. p. 41-42.


    Pranala luar



    Templat:Burgess Shale species
    La evolución de las especies: ¿por qué sobrevivió Pikaia? (Spanish)
    Fossils of the Burgess Shale - Middle Cambrian
    Pikaia gracilens Walcott, a stem-group chordate from the Middle Cambrian of British Columbia
    Templat:Evolusi ikan

Kata Kunci Pencarian:

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Pikaia | Dinopedia | Fandom

Pikaia | Dinopedia | Fandom

Pikaia - the first creature on the Earth

Pikaia - the first creature on the Earth

Pikaia Prehistoric Earth Wiki Fandom, 49% OFF

Pikaia Prehistoric Earth Wiki Fandom, 49% OFF

#Pikaia on Tumblr

#Pikaia on Tumblr

Pikaia - Official Happy Birthdays Wiki

Pikaia - Official Happy Birthdays Wiki

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Pikaia | Design Shack

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Pikaia - The Prehistoric Nature Wiki

Pikaia

Pikaia

pikaia on Tumblr

pikaia on Tumblr

Pikaia! | Anime-Planet

Pikaia! | Anime-Planet

Pikaia_eu (@Pikaia_eu) | Twitter

Pikaia_eu (@Pikaia_eu) | Twitter

Pikaia 3D models - Sketchfab

Pikaia 3D models - Sketchfab

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Pikaia - Wikipedia

Pikaia gracilens is an extinct, primitive chordate marine animal known from the Middle Cambrian Burgess Shale of British Columbia.

Facts and Figures About the Prehistoric Pikaia - ThoughtCo

Apr 8, 2019 · The slender, lancelet-like Pikaia is one of three early fishlike creatures found preserved from the Cambrian period in the geologic record.

Flipping a famous fossil around reveals our earliest vertebrate ... - CNN

Jun 24, 2024 · A new study says scientists were looking at the Pikaia fossil the wrong way. Researchers have long puzzled over the peculiar innards of an ancient sea creature.

Pikaia gracilens - The Burgess Shale

Pikaia – from the pika, a small alpine mammal and cousin of the rabbits. Pikas live in the Rocky Mountains, including near the Burgess Shale. gracilens – from the Latin gracilens, “thin, simple,” in reference to the shape of the body.

A new interpretation of Pikaia reveals the origins of the chordate …

Here we reinterpret the morphology of Pikaia, providing evidence for a gut canal and, crucially, a dorsal nerve cord—a robust chordate synapomorphy. The identification of these structures underpins a new anatomical model of Pikaia that shows that …

Was This Sea Creature Our Ancestor? Scientists ... - The New York Times

Jun 11, 2024 · The researchers now envision Pikaia as a free-swimming animal that searched for particles of food to eat. It apparently lacked eyes, instead using its tentacles to probe its...

The Cambrian fossil Pikaia , and the origin of chordate somites

Feb 1, 2025 · A Pikaia gracilens, from the Middle Cambrian Burgess Shale, a schematic drawing showing the main features discussed here: the small head and associated appendages, possibly gill-related, the series of putative somites, and the dorsal organ (shaded).

What is So Special About Pikaia? All the Ancient Chordate Fuss

Mar 17, 2024 · The remarkable story of the early chordate Pikaia Gracilens starts in 1911 when famous Burgess Shale discoverer, Charles Doolittle Walcott finds a strange-looking “worm/eel-like” fossil in the Canadian Rockies. It’s tiny – just 5cm long – and nowhere near as exciting as the massive Cambrian arthropod monsters he’d found thus far.

Pikaia : A chordate - Understanding Evolution

Pikaia was probably a chordate — the same group that includes fish, dinosaurs, and humans! A fossil Pikaia has a visible notochord and myotomes . Photo by Chip Clark, Museum of Natural History, Smithsonian Institution A zebrafish embryo clearly shows the same structures.

Pikaia - Understanding Evolution

Pikaia grew to four centimeters (about an inch and a half) long. It probably swam close to the sea floor, undulating its body from side to side. Scientists are still trying to figure out what it ate and how it made its living.