TY - JOUR

T1 - Stochastic phenotypic variation

T2 - Empirical results and potential use in Eurytemora research (Copepoda, Calanoida)

AU - Lajus, Dmitry

AU - Sukhikh, Natalia

AU - Alekseev, Victor

N1 - Funding Information: This study was supported by a grant from the Russian Science Foundation 19-14-00092 for D.L.; N.S. and V.A. were supported by a grant from the Russian Foundation for Basic Research 20-04-00035; N.S. was also supported by the Russian Foundation for Basic Research 19-04-00217 and by the national initiative AAAA-A19-119020690091-0. Karen Alexander helped with improving the English. The Federal Collection of the Zoological Institute of the Russian Academy of Sciences (St. Petersburg, Russia) was used for this study. Publisher Copyright: © 2020 Copyright 2020 by Koninklijke Brill NV, Leiden, The Netherlands. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2020/6

Y1 - 2020/6

N2 - This study analyses the potential of stochastic phenotypic variation for investigating the population biology of Eurytemora. Stochastic variation is the third component of phenotypic variance, standing on equal footing with genotypic variation and phenotypic plasticity. This is a manifestation of developmental instability and usually increases under stress. In morphological traits, stochastic variation is most often studied using fluctuating asymmetry (FA) of bilateral traits. Here, using data on the FA of nine populations of three Eurytemora species from Europe and North America, we found no correlation between FA and temperature, salinity or tidal amplitude. Invasive American E. carolleeae in the Gulf of Finland (Baltic Sea) had lower FA than the same species in its native Chesapeake Bay, or than E. affinis in its native Gulf of Finland. This pattern may be caused by global warming, which brought Chesapeake Bay temperatures beyond E. carolleeae's optimal conditions, but made the Gulf of Finland a more suitable environment. Stochastic variation in life history traits is technically more difficult to study, but it may provide important information on fitness. In particular, it manifests in bet-hedging, a risk-spreading strategy beneficial in unpredictable environments. As resting eggs are common in Eurytemora, bet-hedging can be considered a genus strategy. Understanding how stochastic variation contributes to total phenotypic variance may help to interpret changes under unpredictable environmental conditions. Therefore, studies of stochastic phenotypic variation may supply information about the population biology of Eurytemora and other copepods.

AB - This study analyses the potential of stochastic phenotypic variation for investigating the population biology of Eurytemora. Stochastic variation is the third component of phenotypic variance, standing on equal footing with genotypic variation and phenotypic plasticity. This is a manifestation of developmental instability and usually increases under stress. In morphological traits, stochastic variation is most often studied using fluctuating asymmetry (FA) of bilateral traits. Here, using data on the FA of nine populations of three Eurytemora species from Europe and North America, we found no correlation between FA and temperature, salinity or tidal amplitude. Invasive American E. carolleeae in the Gulf of Finland (Baltic Sea) had lower FA than the same species in its native Chesapeake Bay, or than E. affinis in its native Gulf of Finland. This pattern may be caused by global warming, which brought Chesapeake Bay temperatures beyond E. carolleeae's optimal conditions, but made the Gulf of Finland a more suitable environment. Stochastic variation in life history traits is technically more difficult to study, but it may provide important information on fitness. In particular, it manifests in bet-hedging, a risk-spreading strategy beneficial in unpredictable environments. As resting eggs are common in Eurytemora, bet-hedging can be considered a genus strategy. Understanding how stochastic variation contributes to total phenotypic variance may help to interpret changes under unpredictable environmental conditions. Therefore, studies of stochastic phenotypic variation may supply information about the population biology of Eurytemora and other copepods.

KW - INCREASE FLUCTUATING ASYMMETRY

KW - BALTIC SEA

KW - DEVELOPMENTAL INSTABILITY

KW - MORPHOLOGICAL VARIATION

KW - DIRECTIONAL ASYMMETRY

KW - EMBRYONIC-DEVELOPMENT

KW - ATLANTIC COAST

KW - EASTERN GULF

KW - STRESS

KW - AFFINIS

UR - http://www.scopus.com/inward/record.url?scp=85091662385&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/b0582aba-b17d-326e-86f1-c999c2dad3ab/

U2 - 10.1163/15685403-00003983

DO - 10.1163/15685403-00003983

M3 - Article

AN - SCOPUS:85091662385

VL - 93

SP - 317

EP - 336

JO - Crustaceana

JF - Crustaceana

SN - 0011-216X

IS - 3-5

ER -