English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Food and parasites - life-history decisions in copepods

Sivars Becker, L. (2004). Food and parasites - life-history decisions in copepods. PhD Thesis, Uppsala University, Uppsala.

Item is

Basic

show hide
Item Permalink: http://hdl.handle.net/11858/00-001M-0000-000F-DAD8-C Version Permalink: http://hdl.handle.net/11858/00-001M-0000-000F-DAD9-A
Genre: Thesis

Files

show Files
hide Files
:
sivarsbecker_thesis.pdf (Publisher version), 381KB
Name:
sivarsbecker_thesis.pdf
Description:
-
Visibility:
Public
MIME-Type / Checksum:
application/pdf / [MD5]
Technical Metadata:
Copyright Date:
-
Copyright Info:
-
License:
-

Locators

show

Creators

show
hide
 Creators:
Sivars Becker, Lena1, Author              
Kraaijeveld, Alex Robert, Advisor
Affiliations:
1Department Evolutionary Ecology, Max Planck Institute for Evolutionary Biology, Max Planck Society, ou_1445634              

Content

show
hide
Free keywords: life-history; resource allocation; Macrocyclops albidus; cestode infection; Schistocephalus solidus
 Abstract: In the freshwater copepod, Macrocyclops albidus, food availability, rearing conditions and tapeworm infection clearly affected various life-history traits and their trade-offs. I found that low food availability clearly constrained resource allocations to several life-history (often phenotypically plastic) traits, whereas high food availability either allowed for adjustments in resource allocation patterns or allowed to be allocated to several traits withou apparent trade-offs. Both maile and female copepods allocated resources according to food availability; developing more slowly and achieving smaller adult body size when food was scarce. When food availability was low females were constrained and produced fewer eggs (in total and per clutch), and started reproduction later than females with more food available. Males under low food availability allocated reletively more spermatophore size (current reproduction) with decreasing body size. In contrast, when food availability was high males allocated resources to body size as well as spermatophore size. Overall, at maturity, copepods of both sexes were more similar in size than in age, suggesting that large body size was more important for fitness than fast development. In nature the prevalence of copepods infected with cestode tapeworms was found to be low (0-3%). Female copepods, experimentally infected with the cestode Schistocephalus solidus, showed lower overall fecundity, especially when food availability was low. However, infected females produced a larger proportion of their life-time egg production early in life than non-infected females. This might be an adaptation to reduce future fitness costs of infection. Females grown under bad rearing conditions, but with high food availability, produced their first clutch earlier than females grown under good rearing conditions, indicating an adjustment in timing reproduction. These findings contribute to our fundamental evolutionary understanding of how environmental conditions interact with life-history traits.

Details

show
hide
Language(s): eng - English
 Dates: 2004-05-26
 Publication Status: Accepted / In Press
 Pages: 40 Bl.
 Publishing info: Uppsala : Uppsala University
 Table of Contents: Introduction................................................7
Body size.................................................8
Current vs. future reproduction...........................9

Aim........................................................11

Study species..............................................12
The parasite.............................................13
General methods..........................................15

Results and Discussion.....................................17
Age and size at maturity - paper I.......................17
Resource allocation in males - paper II..................19
Female life-histories and food availability - paper III..21
A field study - paper IV.................................23
Resource allocation and cost of infection in females -
paper V................................................. 25

Conclusion.................................................28

Acknowledgments............................................30

Sammanfattning.............................................32

References.................................................36
 Rev. Method: -
 Identifiers: eDoc: 232330
ISBN: 91-554-5971-4
ISSN: 1104-2322X
URI: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4268
Other: Diss/11085
 Degree: PhD

Event

show

Legal Case

show

Project information

show

Source

show