Wednesday, May 13, 2009

Bruguiera gymnorhiza

I am pretty awestruck by this mangrove tree. The contrast of the red calyx against the green of its leaves makes it photogenic. Thanks to the boardwalk at Sg Buloh, one can hold it in your hand and take a picture.

These are unopened.


These are opened


And this is the general habit of the tree. Habit meaning the form - whether its a tree, climber, shrub etc.


It looks festive.

I wonder what pollinates the flowers? Its definitely attractive. Didn't smell it though. I wonder when it flowers in the year. Lots of questions...

More about this plant, the tumu, here

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Nudibranchs and the power of the sun in their tentacles

Saw this cutie at Sentosa today - Polka-dot nudibranch (Jorunna funebris)

Besides nudibranchs, there were a few other people from the seashore groups that were there brought in by the low tide today.

Then I happened to see this slug or is it a nudibranch (someone please) and this dude who happened to be there mentioned that it was a slug that could photosynthesize. I can't verify the species but the nugget about slugs photosynthesizing brought to mind an article I read. But first the pictures of this fair creature... I hope this is really a slug of some sort! I thought they were a cluster of mollusc eggs. I am not sure if this slug really photosynthesizes though.



But anyway, more about photosynthesizing slugs! Well they don't really but they do collect the plastids (chloroplasts basically) by feeding on the algae (they one that this slug is feeding on is presumably Bryopsis). Collecting the plastids is already quite amazing since the slugs selectively do not digest this organelle. Another most profound aspect of this ability to harness photosynthetic machinery is a gene that is co-opted by the slug in its co-evolutionary history... so baby slugs are born with one photosynthetic gene that helps maintain the ingested plastids for at least 9 months... cool.

Solar-powered Sea-slugs Live Like Plants

ScienceDaily (Dec. 3, 2008) — The lowly sea slug, “Elysia chlorotica,” may not seem like the most exciting of creatures, but don’t be fooled

“Photosynthesis needs around 2,000 to 3,000 genes, and animals do not have many of the critical genes,” says Manhart. So Manhart and his co-workers looked into how the plastids consumed by the slug can continue photosynthesizing.

“We found that the slug has at least one gene required for photosynthesis in its nuclear genome, which has never been found in any animal,” says Manhart. “The critical thing is the plastids come from the alga, but the slug nucleus contains at least one, and probably more of the genes required for plastid functioning,” he adds.

Cenchrus brownii

Before I forget again and have to hunt the web for the scientific name!

Cenchrus brownii

Its quite common along the beach forest and it was first recorded in Singapore in 1950. I browsed the www and realised that the plant is in some flickr sets in Singapore without the name (I commented on them).. so here's the name so that the next time someone gets poked by it, at least can curse it properly.

Here's a nice picture of it courtesy of Ria from wildsingapore

It belongs to the grass family and not the sedge family.

Cenchrus brownii!

As you can see, I am pretty invigorated by the fieldtrip I had this morning...

students and Cenchrus

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