Details:

Journal Title:
Global Ecology and Biogeography
Personal Author:
Fernandez, Marina Oliveira ; Collins, Allen G. ; Gittenberger, Arjan ; Roy, Kaustuv ; Marques, Antonio Carlos
Fernandez, Marina Oliveira ; Collins, Allen G. ; Gittenberger, Arjan ; Roy, Kaustuv ; Marques, Antonio Carlos Less -
NOAA Program & Office:
NMFS (National Marine Fisheries Service) ; OST (Office of Science and Technology)
NMFS (National Marine Fisheries Service) ; OST (Office of Science and Technology) Less -
Description:
Aim

Traits affect the survival and reproduction of individuals in different habitat conditions, ultimately altering their distributions. In the oceans, changes in environmental conditions with bathymetry may influence the occurrence of specific traits. Therefore, characterizing trait variation with depth can illuminate drivers related to the distribution of diversity of forms, functions, and life histories. We aimed to investigate patterns of variation in the diversified life histories and morphologies of hydroids with depth, integrating these patterns with the natural history of the group and ecological principles of the deep sea.

Location

Atlantic Ocean and adjacent polar seas, from 50 to 5,330 m deep.

Time period

Present day.

Major taxa studied

Hydrozoa.

Methods

Analyses were based on 14 traits collected for a total of 4,668 specimens of hydroids, belonging to 438 species. Records were divided into 12 depth strata for comparisons. We evaluated: how each trait varies with depth; whether variation in some traits is affected by the presence of other traits; how traits covary; and similarities in trait compositions among depth strata.

Results

Traits of hydroids vary with depth, with more pronounced differences for regions deeper than 1,000 m. Hydroids are generally smaller, infertile, solitary, meroplanktonic, and devoid of protective structures with increasing depth. The relationship, however, is not always linear. Also, some covariation and correlation between traits was evident. For example, depth may affect size differently according to the presence of specific traits such as structures protecting against predation. The lower proportion of fertile specimens recorded in the deep sea suggests that chances for genetic recombination are reduced in deep‐sea populations, ultimately leading to a slower rate of evolution.

Main conclusions

We identified novel trends in hydroid trait variation with depth by combining observations on morphology, ecology, and life history, clarifying selection pressures on hydroids in the deep sea.


Keywords:
[+]
Biogeography Hydrozoa Deep-sea Benthos Marine Biogeography
Source:
Global Ecology and Biogeography 29(5): 908-924, 2020
DOI:
https://doi.org/10.1111/geb.13074
Document Type:
Journal Article
Place as Subject:
Atlantic Ocean
Rights Information:
Accepted Manuscript
Compliance:
Submitted
Main Document Checksum:
[+]
urn:sha256:9531af3d683f8b6b6d9a72c419772674fc3cbc7822b32b4cee379a3e090b1e95
Download URL:
https://repository.library.noaa.gov/view/noaa/29175/noaa_29175_DS1.pdf
File Type:

Supporting Files

• No Additional Files

More +