Showing posts with label Charles Darwin. Show all posts
Showing posts with label Charles Darwin. Show all posts

Tuesday, March 27, 2012

Saving stalked barnacles fixed to a plank










While researching a book about Charles Darwin, I learned of his fascination with barnacles -- in fact, Darwin went on to write two books about this subject alone.

After heavy seas, a few days ago, a plank washed ashore on 'our' beach. It was covered with a colony of stalked barnacles. While photographing them, I noticed movement and realised they were still alive; so Doug carried the plank down to the water's edge and tossed it back into the waves.

These crustaceans attach themselves to hard surfaces such as planks, jetty pylons or rocks. They feed using feathery legs that filter the plankton and other fine food particles from the ocean. Stalked barnacles protect their bodies with a number of hard plates.

Seeing the plank floating out into Western Port Bay -- on a strong current -- gave me a thrill. We'd saved colony of stalked barnacles.

PS
A Pacific gull took advantage of easy food as the plank floated in shallow water.

Friday, October 7, 2011

Charles Darwin's passion for orchids is catching






Followers of my blog will be familiar with the orchid growing in our garden: its origins (as a half -dead (tree trunk) and half- live (clump of orchids) present), and its development from bud through to flowering. This week, my Cymbidium caniculatum is in full glorious bloom.

The name orchid usually brings to mind an exotic display in a florist's window, or lush blossoms in a damp tropical rainforest. The fact that orchids also thrive in the semi-arid country of outback Queensland is something I didn't know until we lived here.

Cymbidium caniculatum (one of about 50 Cymbidium species growing from India to Japan to Australia) has distinctive curved rigid channelled leaves which collect moisture in what is a relatively low rainfall region.

Yesterday I picked a near-perfect orchid bloom and placed it in a vase with the aim of attempting a drawing. Before putting pencil to paper, however, I broke off one of the flowers and pulled it apart: three petals and three petal-like sepals. On looking more closely I saw a column, stigma, cap, ovary and two waxy balls containing pollen. One of the petals, the lip, was larger than the rest, and white. Its purpose is to attract pollinating insects (usually a bee) and then to provide a landing platform -- rather like an airport runway.

My interest in orchids began when I was offered the opportunity to research and write a book about Charles Darwin. Several years later Charles Darwin's Big Idea was published by Hyland House in Melbourne, and was shortlisted in the CBC Awards.

During my research, I became aware of Darwin's fascination with orchids -- and it was catching! Of particular interest to me was the fact that each orchid species attracts its own special kind of insect for pollination.

With up to 60 flowers on each flower spike, the bees are busy around my clump of orchids!