Predator-Mediated Plasticity of Prey Life History and Morphology: Chaoborus americanus Predation on Daphnia pulex

1992 ◽  
Vol 139 (2) ◽  
pp. 229-247 ◽  
Author(s):  
Ken Spitze
Keyword(s):  
Life History ◽  
Daphnia Pulex ◽  
Chaoborus Americanus

Specificity of predator-induced neck spine and alteration in life history traits in Daphnia pulex

Hydrobiologia ◽  
1994 ◽  
Vol 294 (2) ◽  
pp. 129-140 ◽  
Author(s):  
Sari Repka ◽  
Matti Ketola ◽  
Mari Walls
Keyword(s):  
Life History ◽  
Life History Traits ◽  
Daphnia Pulex

Inter- and Intra-specific Variability in the Response of Zooplankton to Acid Stress

1985 ◽  
Vol 42 (11) ◽  
pp. 1749-1754 ◽  
Author(s):  
Edmund E. Price ◽  
Michael C. Swift
Keyword(s):  
Natural Populations ◽  
Daphnia Pulex ◽  
Acid Stress ◽  
Intraspecific Variability ◽  
Early Summer ◽  
Low Ph ◽  
Acid Sensitivity ◽  
Chaoborus Americanus ◽  
Acute Bioassays ◽  
Mesocyclops Edax

We measured the toxicity of sulfuric acid to natural populations of Daphnia pulex, D. galeata mendotae, Simocephalus serrulatus, Mesocyclops edax, Chaoborus americanus, and C. punctipennis. Organisms were collected in the spring and fall from acidic (pH 5.4) and circumneutral (pH 6.3–7.5) ponds, and their response to low pH was compared in 48- or 96-h acute bioassays. Based on 48- and 96-h LC50, cladocerans were most susceptible to acid stress, followed by Mesocyclops and Chaoborus larvae. Simocephalus was the most tolerant cladoceran, followed by D. pulex then D. galeata mendotae. Daphnia populations tested in the spring or early summer were more tolerant of low pH than those tested in the fall. Mesocyclops edax from an acid pond were more tolerant than those from a neutral pond. The response of the two Chaoborus species to low pH were quite similar; their 96-h LC50 (2.00, 2.09) was two pH units lower than those of cladocerans and one pH unit lower than that of M. edax. Our data demonstrate interspecific variability in acid sensitivity and suggest intraspecific variability due to habitat and season.

scholarly journals Loci, genes, and gene networks associated with life history variation in a model ecological organism,Daphnia pulex(complex)

2018 ◽  
Author(s):  
Jacob W. Malcom ◽  
Thomas E. Juenger ◽  
Mathew A. Leibold
Keyword(s):  
Gene Expression ◽  
Genetic Variation ◽  
Life History ◽  
Molecular Basis ◽  
Life History Traits ◽  
Evolutionary Dynamics ◽  
Daphnia Pulex ◽  
Life History Trait ◽  
Life History Variation ◽  
Trait Variation

ABSTRACTBackgroundIdentifying the molecular basis of heritable variation provides insight into the underlying mechanisms generating phenotypic variation and the evolutionary history of organismal traits. Life history trait variation is of central importance to ecological and evolutionary dynamics, and contemporary genomic tools permit studies of the basis of this variation in non-genetic model organisms. We used high density genotyping, RNA-Seq gene expression assays, and detailed phenotyping of fourteen ecologically important life history traits in a wild-caught panel of 32Daphnia pulexclones to explore the molecular basis of trait variation in a model ecological species.ResultsWe found extensive phenotypic and a range of heritable genetic variation (~0 < H2< 0.44) in the panel, and accordingly identify 75-261 genes—organized in 3-6 coexpression modules—associated with genetic variation in each trait. The trait-related coexpression modules possess well-supported promoter motifs, and in conjunction with marker variation at trans- loci, suggest a relatively small number of important expression regulators. We further identify a candidate genetic network with SNPs in eight known transcriptional regulators, and dozens of differentially expressed genes, associated with life history variation. The gene-trait associations include numerous un-annotated genes, but also support several a priori hypotheses, including an ecdysone-induced protein and several Gene Ontology pathways.ConclusionThe genetic and gene expression architecture ofDaphnialife history traits is complex, and our results provide numerous candidate loci, genes, and coexpression modules to be tested as the molecular mechanisms that underlieDaphniaeco-evolutionary dynamics.

The impact of two Chaoborus species on a zooplankton community

1990 ◽  
Vol 68 (5) ◽  
pp. 981-985 ◽  
Author(s):  
Neil A. MacKay ◽  
Stephen R. Carpenter ◽  
Patricia A. Soranno ◽  
Michael J. Vanni
Keyword(s):  
Chlorophyll A ◽  
Daphnia Pulex ◽  
Zooplankton Community ◽  
Chlorophyll A Concentration ◽  
Chaoborus Flavicans ◽  
Chaoborus Americanus ◽  
Diaptomus Oregonensis ◽  
Herbivore Responses ◽  
The Impact

The responses of a zooplankton community to Chaoborus predation were studied in large in situ mesocosms in Peter Lake. Chaoborus flavicans, the native chaoborid, significantly reduced the density of the dominant grazer, Daphnia pulex, in relation to controls that lacked Chaoborus. Chaoborus americanus, a species found only in fishless bogs, reduced Da. pulex densities far more than the chaoborid found in Peter Lake, C. flavicans. Chaoborus americanus also significantly reduced the dominant copepod, Diaptomus oregonensis, in relation to both the control and the C. flavicans treatment. Chlorophyll a concentration did not differ among treatments, indicating that herbivore responses could not be explained by changes in food levels. Our results show that Chaoborus predation can greatly affect a zooplankton community, especially daphnids.

Sign in / Sign up

Export Citation Format

Share Document