It is amazing how much of the world we know is actually practically invisible. We all know that the surface of the
Earth is seven-tenths water, of course*. And in that, mostly ocean, there are tunas and sea turtles and corals and barnacles. But really, what is important it seems is the small stuff. The stuff that is
so abundant, that despite the tiny size there is enough to feed a lot of blue whales.
What I'm talking about are the plankton. There are two types (I think): plant (phytoplankton) and animal (zooplankton). Yes, there are protists, and viruses, and other microbes in the sea, and they get digested with the whole mass of stuff that gets mashed against the baleen of a whale to make a nutrient smoothie. But we are going to focus on the multicellular fun of the ocean, and how it moves around, and mostly how we don't know that well about how it moves around.
There are three components, none of which we understand all that well. At least, to my liking.
- The life history of the plankton. Understanding this first involves separating alga from animal, and then a number of factors including size, and temperature during development, and what this thing eats or needs, come into the equation. Basically, though, what we generally know little about, and have a lot of uncertainty about, is why it develops in the length of time that it does from zygote to adult, what it needs, to what extent it is a passive floating particle in the ocean or an active swimmer with behavior that is important to its survival, and where it goes while it is developing from a small number of cells to a large number of cells with distinct function.
- Where it goes while it is developing depends not so much on behavior - but that is important - as on the movement of water in the ocean. The viscosity of fluids is important when you are small, and most of these plankton are on the order of a few hundreds of micrometers at their largest. That means that where the water moves, they get carried along. This is important in a lot of ways.
- At a certain scale - I'm talking about time scale as well as spatial scale - the movement of individuals within populations of larvae (another way to think about plankton, in many animals they are the young versions of adults we find on the seafloor) influences how the distinct architecture created by environmental and genetic influences (note the double-usage of "influence", each time suggesting uncertainty) can be associated with its place of origin, of development, of maturation, of existence as an adult. That is a long sentence that leads us to think about how individuals can be adapted to a particular environment, and that is a pretty complex subject.
- Finally, that environment is changing. Has changed. Of course, I'm talking about climate change, but it is so much deeper than the "global warming" phrase; climate change encompasses how chemical change in the atmosphere and ocean lead to increased sea surface temperature, ocean acidification, altered weather and climate patterns, and many other effects.
I just listed four things that all interact - or are they four different ways of describing the same phenomenon? - but all have a great deal of uncertainty surrounding each topic. Here is the key question: how does each one interact in a way that, by informing each other, we reduce that uncertainty enough to understand the whole problem, and what to do or what to study next?
This is evolutionary oceanography. It is the study of how variance, and uncertainty, in the description of many interacting things, lets us understand better what the ocean is, biologically, what it is doing, and what it will become. I am exploring this topic on the web, using a wiki, because that lets me pull together the resources that are visual, data-rich, and correct as quickly as possible. Here is my outline:
- What's Larvae Got To Do With It?
- The Motion of the Ocean
- The Marine Synthesis
- Wish I'd Paid More Attention in Biochem
What's Larvae Got To Do With It?
Of course, I'll start off first by thanking my colleague Peter Marko. Not only have I blatantly ripped off one of the best titles for a scientific paper ever, but Peter is one my colleagues who pushed me to think about how larvae are not just larvae, but eventual adults. Remember, we are talking about marine organisms, and most marine creatures have a biphasic life cycle. Here I am using "creatures" loosely: always keep in mind there are unicellular beasts that can kill you, kelp that are simple but could be laid out along a soccer field an impressive distance, and metazoan life that moves slowly but still fulfills the basic tenets of ecology: eat or be eaten. Even among the top predators of the marine invertebrate world (I'm leaving the fish aside here, charismatic, quick-moving, and tasty though they are), there are top-top predators like Pycnopodia seastars willing to eat anything in their path, including other seastars.
So anyway, these larvae - that become adults - have an ecology. They have behavior. They are individuals. They, my friend, are corporations, as former presidential candidate Mitt Romney said. Wait. Something is backwards. But it works, still. Every individual is a member of a population, which is part of a species; and every individual is incorporated (
Merriam Webster,
united in one body) through proteins and associated cellular complexes, generated by the genetic architecture of that organism, and that involves genes, which involves different mutations.... it gets complicated. We will get there soon enough.
*never mind what some editors at big fancy journals have told me about the "generality" of work I've done with colleagues on marine biodiversity, evolution, et cetera
Evolution and Climate Change in the Oceans
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