Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Macroscopic sexual dimorphism in Fucus radicans (Phaeophyceae) with implications for its reproductive ecology
Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
Number of Authors: 2
2016 (English)In: Botanica Marina, ISSN 0006-8055, E-ISSN 1437-4323, Vol. 59, no 6, 485-490 p.Article in journal (Refereed) Published
Abstract [en]

Sexual dimorphism on a macroscopic scale is unusual within the Phaeophyceae. We report for the first time macroscopic sexual dimorphism in Fucus radicans. A set of morphological characters was measured on three dioecious Fucus species, F. radicans, Fucus serratus and Fucus vesiculosus, to determine if sexual dimorphism occurs in the endemic F. radicans in the Baltic Sea and if it also is found in the other fucoids. F. radicans was sampled from highly clonal populations of the Bothnian Sea and from populations in the Vainameri Sea where no clones have been found. In both locations, sexual dimorphism was recorded in receptacle size and weight in F. radicans. Also, the receptacle dry weight to wet weight ratio was higher in males than in females, showing that male receptacles have a lower water content than females. The dimorphism was more pronounced in the Bothnian Sea populations, where further differences between the sexes in thallus width and fertility index also were present. This has not been shown for any member of the genus Fucus before, but seems to be a species-specific character in F. radicans, as there were no differences between the sexes in either F. serratus or F. vesiculosus.

Place, publisher, year, edition, pages
2016. Vol. 59, no 6, 485-490 p.
Keyword [en]
clonality, fertility index, morphology, receptacles, reproductive allocation
National Category
Biological Sciences
Research subject
Plant Ecology
Identifiers
URN: urn:nbn:se:su:diva-137611DOI: 10.1515/bot-2016-0046ISI: 000388584400009OAI: oai:DiVA.org:su-137611DiVA: diva2:1063726
Available from: 2017-01-10 Created: 2017-01-09 Last updated: 2017-01-10Bibliographically approved
In thesis
1. On the endemic Fucus radicans in the Baltic Sea
Open this publication in new window or tab >>On the endemic Fucus radicans in the Baltic Sea
2015 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The brown macroalgae Fucus radicans is endemic to the Baltic Sea, but little is known about this newly described species. This thesis investigates the ecology and role of F. radicans within the species poor Baltic Sea ecosystem. The thallus of F. radicans had a more complex structure but was smaller than F. vesiculosus, the other important foundation species with which it grows in sympatry at several sites. The variability of the associated flora and fauna communities of these two Fucus species, however, was explained by the thallus size, not the complexity. Comparisons between the populations of F. radicans in the Bothnian Sea with those in Väinameri Sea on the Estonian coast, showed that the Estonian thalli were smaller, less complex and lacking the numerous adventitious branches which occur extensively in the Bothnian Sea populations.

The distribution of F. radicans in Sweden is limited to the Bothnian Sea coast. The low salinity at the northern limit prevented successful fertilization, while increased salinity did not restrict F. radicans but improved its reproductive success. The southern distribution limit was instead shown to be negatively impacted by a combination of grazing and competition. The asexual reproduction through settling of detached fragments was favoured by high light levels and high temperature in laboratory conditions. Re-attachment occurred by basally formed rhizoids but settling also occurred through a calcium-rich substance, seemingly secreted by the fragment. Genetic spatial distribution of F. radicans showed a dominance of a few widespread clones both within and between sites with an intermingled rather than clustered pattern. The extensive female clone, common in most sites, is most likely old and several clonal lineages have derived from her.  Although more clearly expressed in the clonal populations, the macroscopic sexual dimorphism discovered appears to be a species specific trait in F. radicans. This thesis presents further insight in F. radicans role within the Baltic Sea ecosystem and its value as a study species for adaptation, clonality and speciation.

Place, publisher, year, edition, pages
Stockholm: Department of Ecology, Environment and Plant Sciences, Stockholm University, 2015. 66 p.
Keyword
seaweed, sexual reproduction, clonality, fragmentation, dimorphism, salinity, distribution
National Category
Natural Sciences
Research subject
Plant Ecology
Identifiers
urn:nbn:se:su:diva-117584 (URN)978-91-7649-196-6 (ISBN)
Public defence
2015-09-18, Nordenskiöldsalen, Geovetenskapens hus, Svante Arrhenius väg 12, Stockholm, 09:30 (English)
Opponent
Supervisors
Funder
Swedish Research Council Formas
Note

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Manuscript. Paper 4: Manuscript. Paper 5: Manuscript.

Available from: 2015-06-11 Created: 2015-05-25 Last updated: 2017-01-10Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Schagerström, EllenKautsky, Lena
By organisation
Department of Ecology, Environment and Plant Sciences
In the same journal
Botanica Marina
Biological Sciences

Search outside of DiVA

GoogleGoogle Scholar

Altmetric score

Total: 12 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf