Abstract
Aim
Lanternfishes (Myctophidae) are one of the most species-rich families of mid-water fishes. They inhabit the mesopelagic zone, where physical barriers to dispersal and gene flow are permeable. Thus, modes of speciation that rely exclusively on geographical separation are potentially of less importance than those that rely more prominently on evolution of assortative mating through divergent habitat use and/or sexual signals, including visual signals from bioluminescent light organs. Here we used phylogenetic, ecological and morphological data to investigate the roles of geography, habitat use and lateral photophores in lanternfish speciation.
Location
Global.
Time period
Data collected between 1950 and 2015.
Major taxa studied
Lanternfishes (Myctophidae).
Methods
Ecological niche models (ENMs) were developed for 167 species, enabling the community composition of 33 mesopelagic ecoregions to be determined. Sequence data for seven protein-coding regions from 175 species were used to reconstruct a phylogenetic tree of Myctophidae. Age-overlap correlation tests were conducted using this phylogeny with outputs from ENMs (pairwise geographical overlap and pairwise ecological niche overlap, n = 136), in addition to matrices of pairwise depth overlap (n = 158) and photophore pattern dissimilarity (n = 161).
Results
Communities assembled according to nine broad climatic regions, and recently diverged species pairs possessed greater geographical and ecological niche overlap than more distantly related species, indicating that sympatric or parapatric speciation might be dominant modes of divergence. Differences in photophore patterns increased with the relative age of speciation events, suggesting that photophore patterns are largely constrained by phylogeny.
Main conclusions
Based on this evidence, we suggest that large-scale oceanographic features structure the diversity of lanternfish communities and that speciation within this family of deep-water fishes might not have required geographical isolation.
Lanternfishes (Myctophidae) are one of the most species-rich families of mid-water fishes. They inhabit the mesopelagic zone, where physical barriers to dispersal and gene flow are permeable. Thus, modes of speciation that rely exclusively on geographical separation are potentially of less importance than those that rely more prominently on evolution of assortative mating through divergent habitat use and/or sexual signals, including visual signals from bioluminescent light organs. Here we used phylogenetic, ecological and morphological data to investigate the roles of geography, habitat use and lateral photophores in lanternfish speciation.
Location
Global.
Time period
Data collected between 1950 and 2015.
Major taxa studied
Lanternfishes (Myctophidae).
Methods
Ecological niche models (ENMs) were developed for 167 species, enabling the community composition of 33 mesopelagic ecoregions to be determined. Sequence data for seven protein-coding regions from 175 species were used to reconstruct a phylogenetic tree of Myctophidae. Age-overlap correlation tests were conducted using this phylogeny with outputs from ENMs (pairwise geographical overlap and pairwise ecological niche overlap, n = 136), in addition to matrices of pairwise depth overlap (n = 158) and photophore pattern dissimilarity (n = 161).
Results
Communities assembled according to nine broad climatic regions, and recently diverged species pairs possessed greater geographical and ecological niche overlap than more distantly related species, indicating that sympatric or parapatric speciation might be dominant modes of divergence. Differences in photophore patterns increased with the relative age of speciation events, suggesting that photophore patterns are largely constrained by phylogeny.
Main conclusions
Based on this evidence, we suggest that large-scale oceanographic features structure the diversity of lanternfish communities and that speciation within this family of deep-water fishes might not have required geographical isolation.
| Original language | English |
|---|---|
| Pages (from-to) | 2353-2367 |
| Number of pages | 15 |
| Journal | Global Ecology and Biogeography |
| Volume | 31 |
| Issue number | 11 |
| Early online date | 18 Sept 2022 |
| DOIs | |
| Publication status | E-pub ahead of print - 18 Sept 2022 |
Bibliographical note
Funding Information:This work was supported by a Natural Environment Research Council studentship to J.J.F. [NE/L002434/1] and a Worldwide Universities Network Research Mobility Grant. We thank Dr Dianne Bray (Museum Victoria), Dr Fanny de Busserolles (University of Brisbane) and Dr Gabi Stowasser (British Antarctic Survey) for donating tissue samples for phylogenetic analyses, and Dr John Paxton (Australian Museum) for sharing invaluable literature that was used in validating occurrence records. We acknowledge Joshua Adamson, Declan Lagan and Zev Anderson for their help with compiling the taxonomic images and for their efforts in creating the pairwise depth overlap matrix.
Funding Information:
This work was supported by a Natural Environment Research Council studentship to J.J.F. [NE/L002434/1] and a Worldwide Universities Network Research Mobility Grant. We thank Dr Dianne Bray (Museum Victoria), Dr Fanny de Busserolles (University of Brisbane) and Dr Gabi Stowasser (British Antarctic Survey) for donating tissue samples for phylogenetic analyses, and Dr John Paxton (Australian Museum) for sharing invaluable literature that was used in validating occurrence records. We acknowledge Joshua Adamson, Declan Lagan and Zev Anderson for their help with compiling the taxonomic images and for their efforts in creating the pairwise depth overlap matrix.
Publisher Copyright:
© 2022 The Authors. Global Ecology and Biogeography published by John Wiley & Sons Ltd.
Fingerprint
Dive into the research topics of 'Global phylogeography of hyperdiverse lanternfishes indicates sympatric speciation in the deep sea'. Together they form a unique fingerprint.Cite this
- APA
- Author
- BIBTEX
- Harvard
- Standard
- RIS
- Vancouver