I. Diagnostic Characters of the Brown Algae.
|How many are there? about 265 genera with about 2000 species.|
|How old are they? probably not more than 200 million years old with some at 65 myo.|
|Where are brown algae found?
|How are their cells organized? Uninucleate organization throughout all cells.|
|What pigments do they possess?
|How is the chloroplast constructed?
|What storage product is made?
|Cell wall features?
|Cell and thallus complexity?
II. Simplest cell construction.
Ectocarpus filaments and production of motile cells via plurilocular structures.
III. Developmental lineages and comparative life history strategies.
Simple to increasingly complex (Order Ectocarpales) with intermediate life history.
All of these genera reproduce via the Sporic Meiosis Life History.
Increasingly complex adult morphologies (Order Dictyotales) and intermediate life history
All of these genera reproduce via the Sporic Meiosis Life History
Most complex adult morphology (Order Fucales) and most advanced life history
All of these genera reproduce via the Gametic Meiosis Life History
IV. Recap major themes
Increasing complexity shown in adult morphologies and life history strategies.
Gamete type is extremely conservative character.
Most advanced orders possess modified male gametes.
|Brown Algae, UC Berkeley||What's the Sargasso Sea?|
|California brown algae, Sonoma State University||Kelp Tank Exhibit, Monterey Bay Aquarium's Kelp Cam|
This page is maintained by Celia Smith and intended for use by undergraduates and graduates, Botany Dept, Univ Hawai'i at Manoa.