Monday, July 27, 2020

Little boxes

A couple of days ago, walking with family down on the docks, spotting starfish and anemones, I saw a long streamer of kelp, loaded with bryozoan colonies, almost within my reach. My son fished it out for me.

At home, I examined it, using a lens, then the microscope, finally the camera, when the light was better.

First: the colonies themselves:

Small bryozoan colony, Membranipora membranacea

These bryozoans are tiny animals, each living in its own rectangular, glassy box. The animal inside extends its tentacles (called a lophophore) through a hole at one end of the box, capturing food from the plankton; bacteria, diatoms, and other small floaters.

Little cubicles. Each one holds one zooid.

Looking at a colony on a curve.

A colony, happily feeding.

Another side view. Look closely (or click for full size) to see the individual animals.

Out of the water, the whole colony shuts itself inside its walls. Put them in water, and in a few seconds, the first ones are out, opening and shutting, capturing dinner.

These were some of the camera shots. Tomorrow, the microscope views, and what I found there.


El sábado fui con familia a caminar en el muelle, mirando estrellas de mar y anémonas bajo los flotadores. Vi  una hoja larga de alga marina "kelp", cubierta de manchas blancas. Mi hijo me la capturó y la traje a casa para examinarla.

La hoja estaba poblada por gran cantidad de colonias de un briozoo, Membranipora membranacea. Son animales pequeños que se hacen cajitas blancas, casi transparentes; cada animal vive en una caja. Tiene un agujero a un extremo, y por medio de este, (el lofóforo) el animalito extiende sus tentáculos para capturar su presa, que son bacteria, diatomeas, y otros criaturas del plancton.

Fuera del agua, toda la colonia se encierra en sus cajitas. En el agua, inmediatamente, se levantan y empiezan a mover sus tentáculos, capturando la cena.

Estas fotos son algunas que saqué con la cámara; además, examiné las colonias con el microscopio. Mañana subo algunas de esas fotos, con algunos otros animales que viven alrededor del briozoo.

1 comment:

  1. Thanks Susannah, I've not seen these before. I look forward to the microscopic views.


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