Grazer-induced colony formation in Scenedesmus: are there costs to being colonial?

TY - JOUR

T1 - Grazer-induced colony formation in Scenedesmus: are there costs to being colonial?

AU - Lürling, M.

AU - Van Donk, E.

N1 - Reporting year: 2000 Metis note: 2577; CL; AFW ; AqE; file:///L:/Endnotedatabases/NIOOPUB/pdfs/Pdfs2000/Lurling_ea_2577.pdf

PY - 2000

Y1 - 2000

N2 - Grazer-induced colony formation in the common green alga Scenedesmus acutus may be interpreted as an anti-grazer defense. Costs are to be expected because otherwise the protected colonial morph would be the norm. Analysis of growth rates, light harvesting in terms of photosystem II (PSII) efficiency using Xe-PAM fluorescence measurements and sedimentation rates were compared among unicellular and induced colonial populations. No differences in growth rates and PSII efficiency were detected between unicellular and colonial populations. However, colonial populations had higher settling velocities than unicellular populations. Hence, costs may be attributed to enhanced sinking out of the euphotic zone resulting in reduced growth due to lower light and temperature in deeper water layers. [KEYWORDS: Morphological-changes; inducible defenses; crucian carp; green- algae; in-situ; phytoplankton; daphnia; chlorophyceae; sinking; growth]

AB - Grazer-induced colony formation in the common green alga Scenedesmus acutus may be interpreted as an anti-grazer defense. Costs are to be expected because otherwise the protected colonial morph would be the norm. Analysis of growth rates, light harvesting in terms of photosystem II (PSII) efficiency using Xe-PAM fluorescence measurements and sedimentation rates were compared among unicellular and induced colonial populations. No differences in growth rates and PSII efficiency were detected between unicellular and colonial populations. However, colonial populations had higher settling velocities than unicellular populations. Hence, costs may be attributed to enhanced sinking out of the euphotic zone resulting in reduced growth due to lower light and temperature in deeper water layers. [KEYWORDS: Morphological-changes; inducible defenses; crucian carp; green- algae; in-situ; phytoplankton; daphnia; chlorophyceae; sinking; growth]

U2 - 10.1034/j.1600-0706.2000.880113.x

DO - 10.1034/j.1600-0706.2000.880113.x

M3 - Article

SN - 0030-1299

VL - 88

SP - 111

EP - 118

JO - Oikos

JF - Oikos

IS - 1

ER -