请输入您要查询的百科知识：

　

词条 Holochroal eye
释义

  1. References

Holochroal eyes are compound eyes with many tiny lenses (sometimes more than 15,000, each 30-100μm, rarely larger).[1] They are the oldest and most common type of trilobite eye,[2] and found in all orders of trilobite from the Cambrian to the Permian periods. Lenses (composed of calcite) covered a curved, kidney-shaped visual surface in a hexagonal close packing system, with a single corneal membrane covering all lenses.[3] Unlike in schizochroal eyes, adjacent lenses were in direct contact with one another.[4] Lens shape generally depended on cuticle thickness. The lenses of trilobites with thin cuticles were thin and biconvex, whereas those with thick cuticles had thick lenses, which in extreme cases, could be thick columns with the outer surface flattened and the inner surface hemispherical.[4] Regardless of lens thickness, however, the point at which light was focused was roughly the same distance below the lens.[4]

References

1. ^{{Citation | last1 = Clarkson | first1 = E. N. K. | year=1979 | title =The Visual System of Trilobites.| journal =Palaeontology |volume= 22 |pages=1–22}}
2. ^{{citation | author = Schoenemann, B. | title = Trilobite Eyes and a New Type of Neural Superposition Eye in an Ancient System |date=October 2007 | journal = Palaeontographica Abt. A | volume = 281 | issue = 1–3 | pages = 63–91 | publisher = Verlag| doi = 10.1127/pala/281/2007/63 }}
3. ^{{Citation | last = Clarkson | first = E.N. | contribution = The Eye, Morphology, Function and Evolution | editor-last = Kaesler | editor-first = R.L. (ed) | title = Treatise on Invertebrate Paleontology, Part O, Arthropoda 1, Trilobita, revised. Volume 1: Introduction, Order Agnostida, Order Redlichiida | pages = 114–132 | publisher = The Geological Society of America, Inc. & The University of Kansas | place = Boulder, CO & Lawrence, KA | year = 1997 | isbn = 978-0-8137-3115-5}}
4. ^1 2 {{Cite journal|last=Clarkson|first=Euan|last2=Levi-Setti|first2=Riccardo|last3=Horváth|first3=Gabor|year=2006|title=The eyes of trilobites: The oldest preserved visual system|journal=Arthropod Structure & Development|volume=35|issue=4|pages=247–259|doi=10.1016/j.asd.2006.08.002|pmid=18089074}}
{{vision in animals}}{{trilobite-stub}}

2 : Eye|Animal anatomy
随便看

　

开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。

　

Copyright © 2023 OENC.NET All Rights Reserved
京ICP备2021023879号 更新时间：2024/9/20 17:39:19