Evidence map›Paper›PMID 39562764›Full record

ArticleNature communications2024

Heart cockle shells transmit sunlight to photosymbiotic algae using bundled fiber optic cables and condensing lenses.

Dakota E McCoy, Dale H Burns, Elissa Klopfer, Liam K Herndon, Babatunde Ogunlade, Jennifer A Dionne, Sönke Johnsen

Abstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in Nature communications, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors.

Dakota E McCoyDepartment of Ecology and Evolution, The University of Chicago, Chicago, IL, USA. dakota.e.mccoy@gmail.com.ORCID 0000-0001-8383-8084
Dale H BurnsDepartment of Earth and Planetary Sciences, Stanford University, Stanford, CA, USA.
Elissa KlopferDepartment of Materials Science and Engineering, Stanford University, Stanford, CA, USA.
Liam K HerndonDepartment of Chemical Engineering, Stanford University, Stanford, CA, USA.
Babatunde OgunladeDepartment of Materials Science and Engineering, Stanford University, Stanford, CA, USA.
Jennifer A DionneDepartment of Materials Science and Engineering, Stanford University, Stanford, CA, USA. jdionne@stanford.edu.ORCID 0000-0001-5287-4357
Sönke JohnsenDepartment of Biology, Duke University, Durham, NC, 27708, USA. sjohnsen@duke.edu.ORCID 0000-0002-3943-8320

Funding

National Science Foundation (NSF) 2109465
6 · The paper itself

Abstract

Many animals convergently evolved photosynthetic symbioses. In bivalves, giant clams (Cardiidae: Tridacninae) gape open to irradiate their symbionts, but heart cockles (Cardiidae: Fraginae) stay closed because sunlight passes through transparent windows in their shells. Here, we show that heart cockles (Corculum cardissa and spp.) use biophotonic adaptations to transmit sunlight for photosynthesis. Heart cockles transmit 11-62% of photosynthetically active radiation (mean = 31%) but only 5-28% of potentially harmful UV radiation (mean = 14%) to their symbionts. Beneath each window, microlenses condense light to penetrate more deeply into the symbiont-rich tissue. Within each window, aragonite forms narrow fibrous prisms perpendicular to the surface. These bundled "fiber optic cables" project images through the shell with a resolution of >100 lines/mm. Parameter sweeps show that the aragonite fibers' size (~1 µm diameter), morphology (long fibers rather than plates), and orientation (along the optical c-axis) transmit more light than many other possible designs. Heart cockle shell windows are thus: (i) the first instance of fiber optic cable bundles in an organism to our knowledge; (ii) a second evolution, with epidermal cells in angiosperm plants, of condensing lenses for photosynthesis; and (iii) a photonic system that efficiently transmits useful light while protecting photosymbionts from UV radiation.

Indexed as

CardiidaePhotosynthesisSunlightSymbiosisAnimalsFiber Optic TechnologyUltraviolet Rays

Identifiers

PMID39562764
PMCPMC11576985

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.