scholarly journals Disparate compound eyes of Cambrian radiodonts reveal their developmental growth mode and diverse visual ecology

2020 ◽  
Vol 6 (49) ◽  
pp. eabc6721
Author(s):  
John R. Paterson ◽  
Gregory D. Edgecombe ◽  
Diego C. García-Bellido

Radiodonts are nektonic stem-group euarthropods that played various trophic roles in Paleozoic marine ecosystems, but information on their vision is limited. Optical details exist only in one species from the Cambrian Emu Bay Shale of Australia, here assigned to Anomalocaris aff. canadensis. We identify another type of radiodont compound eye from this deposit, belonging to ‘Anomalocaris’ briggsi. This ≤4-cm sessile eye has >13,000 lenses and a dorsally oriented acute zone. In both taxa, lenses were added marginally and increased in size and number throughout development, as in many crown-group euarthropods. Both species’ eyes conform to their inferred lifestyles: The macrophagous predator A. aff. canadensis has acute stalked eyes (>24,000 lenses each) adapted for hunting in well-lit waters, whereas the suspension-feeding ‘A.’ briggsi could detect plankton in dim down-welling light. Radiodont eyes further demonstrate the group’s anatomical and ecological diversity and reinforce the crucial role of vision in early animal ecosystems.

Development ◽  
1981 ◽  
Vol 66 (1) ◽  
pp. 159-174
Author(s):  
Charles Straznicky ◽  
David Tay

Right compound eyes were formed in Xenopus embryos at tailbud stages by the fusion of two nasal (NN), two temporal (TT) or two ventral (VV) halves. The left eye was kept intact. Two to four weeks after metamorphosis the optic nerve from the intact eye was severed to induce bilateral optic nerve regeneration. The contralateral retinotectal projections from the compound eye and the induced ipsilateral projections from the intact eye to the same (dually innervated) tectum were studied by [3H]proline autoradiography and visuotectal mapping from 3 to 6 months after the postmetamorphic surgery. The results showed that the NN, TT and VV projections, in the presence of optic fibres from the intact eye failed to spread across the whole extent of the dually innervated tectum. Unexpectedly the bulk of the regenerating projection from the intact eye was confined to the previously uninnervated parts of the dually innervated tecta, the caudomedial region in TT, the rostrolateral region in NN and the lateral region in VV eye animals. The partial segregation of the two populations of optic fibres in the dually innervated tectum has been taken as a further indication of the role of fibre-fibre and fibre-tectum interactions in retinotectal map formation.


2021 ◽  
Author(s):  
Blayze F Millward ◽  
Steve Maddock ◽  
Michael Mangan

Revealing the functioning of non-standard visual systems such as compound eyes is of interest to biologists and engineers alike. A key investigative method is to replicate the sensory apparatus using artificial systems, allowing for investigation of the visual information that drives animal behaviour when exposed to environmental cues. To date, 'Compound Eye Models' (CEMs) have largely explored the impact of features such as spectral sensitivity, field of view, and angular resolution on behaviour. Yet, the role of shape and overall structure have been largely overlooked due to modelling complexity. However, modern real-time raytracing technologies are enabling the construction of a new generation of computationally fast, high-fidelity CEMs. This work introduces new open-source CEM software (CompoundRay) alongside standardised usage techniques, while also discussing the difficulties inherent with visual data display and analysis of compound eye perceptual data. CompoundRay is capable of accurately rendering the visual perspective of a desert ant at over 5,000 frames per second in a 3D mapped natural environment. It supports ommatidial arrangements at arbitrary positions with per-ommatidial heterogeneity.


2001 ◽  
Vol 11 (PR11) ◽  
pp. Pr11-47-Pr11-52
Author(s):  
V. M. Pan ◽  
V. S. Flis ◽  
V. A. Komashko ◽  
O. G. Plys ◽  
C. G. Tretiatchenko ◽  
...  

Jurnal Akta ◽  
2017 ◽  
Vol 4 (3) ◽  
pp. 463
Author(s):  
Muslim Ansori ◽  
Akhmad Khisni

With the enactment of the Education System Act no 20 of 2003 (better known as the Sisdiknas Act), the State has determined that educational institutions should have a legal umbrella in the form of a legal entity, or better known as the Legal Entity Education. As a non-profit organization, the Foundation is the right legal entity that becomes a place for educational institutions, especially private schools. Therefore, of course, Notary has a very crucial role in making notary deed in the form of establishment and deed of change, such as example how in making the right basic budget and not multi interpresatasi for stake holders in the foundation. Therefore, the role of function and authority of the organ of the foundation must be clearly stated in the articles of association, so as not to cause a dispute in the future.KEYWORDS: Notaries, Foundation, Organ Foundation,


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