Wednesday, October 14, 2009

Mangels, Mangroves, Zonation, and Shrimp, Glorious Shrimp!

We're talking tides in Marine Science this week ... spring tides, neap tides, semidiurnal tides, diurnal tides, mixed tides ... what they are, why they are, differences, effects on marine life ... it's mind boggling.


At least I think their minds are boggled ... it's hard to tell on some of them.


Sometimes, when dealing with these simple truths about planet Earth, I take the opposite tack and ask them to imagine a world without whatever natural process or truth that we are dealing with at the time..


What if there were no tides on earth? How different would things be for life along the coast ... and for us?


... Or when we are discussing all the WEIRD properties of that chemical bad boy ... water ... what a rebel compound this water stuff is ... incorrigible actually.



It breaks so many rules ... like that crazy density thing ... being less dense as a solid than as a liquid. TOTALLY WEIRD.



I ask them ...

"What if ice sunk like it's supposed to do?"



We range far and wide over the global effects of billions of years of ice sinking, piling up on the seafloor, cooling the waters ever more, creeping outward ... and we usually wind up realizing that the simple fact that ice floats makes it possible for us to be here in our present form.



That and the fact that Peggy Flemming or Dorothy Hamill would never have had a sport to participate in is pretty sobering.





But, what of tides and mangels of mangroves manifesting multiarching roots with many multitudes of munchers mingling amongst them?

What of sessile stress?


The sessile dilemma ...
Where to live, where to live ?
If I attach too high, I'd better be tough enough to withstand hours outside of water during falling tides. Plus, I will be stuck there in plain view of interlopers like raccoons and other munchers.




If I attach deep, I won't have to worry about dessication, but the competition for space is tough and there will be constant threats from aquatic predators.

Just be thankful there are SO many proproots to choose from sessile citizens. The mangrove is very generous in this area.


Leaving sessile stress behind, we arrive in the mud where the value of the mangrove tree shines again in the form of detritus.


Every detrital mangrove leaf adds to the nutrients in the mud, which provides a feast for microorganisms that become fodder for shrimp and THAT, dear readers, is a very fine thing.




A VERY FINE THING.




7 comments:

Doug Taron said...

I enjoyed your comments about teaching middle schoolers about the weirdness that is water. Years ago I took a graduate-level course in physical biochemistry. The whole first week's worth of lectures was about the strange properties of good ol' H2O.

Tides are the thing that I miss the most about no longer living near the ocean.

cndymkr / jean said...

I've been snacking on shrimp all day today. Stop peeking in my window. It was on sale and just begging to eaten.

Did it MY way said...

Ah reason number 2000 or so for living in paradise.

Miz S said...

I never thought about ice floating before!! Never even once!! You have just rocked my universe.

Deb said...

Without floating ice, Minnesotans would not be able to do crazy things like drive on lakes and erect mini ice fishing villages.

Floridacracker said...

Doug,
All high school classes this year ... first time in 20 years.
Got your email. Will reply soon.

Jean,
Pass the plate.

Did it,
Oh yeah!

Miz S,
You will never be able to look at the ice in your drink in the same way.
I just love rocking people's universes. Thanks!!

Deb,
Exactly! Think of the stories that would not get told by freezing people huddled around small holes in the ice.

amarkonmywall said...

Well, I think you exaggerate. That shrimp is not a very fine thing YET. Maybe someday- but now he looks closer to krill. Or something they serve at all-you-can-eat shrimpfest at Red Lobster.