Comments on: Meet our Chefs

By: Steven Tuorto

Steven Tuorto — Fri, 06 Jun 2014 20:01:56 +0000

Dear Kyle – I know! Gross, right! Well, my interest in zooplankton poops dates back a couple years to when I read a scientific paper. The paper showed a close connection between the annual growth of a clam and the local abundance of this one large copepod species. In other words, when we had a year with lots of this one copepod species, the clam also grew a lot that year; and vise versa! My advisor and I started discussing this close connection. Clams do not eat copepods directly, so that couldn’t explain the relationship. We started thinking that maybe the clams were eating copepod fecal pellets, and that these larger pellets (from this one large copepod species) were reaching the clam because they sink faster than small pellets. When copepods egest (poop), their fecal pellets are often full of undigested phytoplankton, the stuff clams usually feed on. I started reading about sinking zooplankton fecal pellets, trying to unravel this little clam-copepod mystery. It turns out that sinking zooplankton fecal pellets are sometimes an important component of biological material sinking from the upper ocean, where they are produced, to the deep ocean. When biological material, which is carbon-based, sinks deep enough, the carbon is taken out of the ocean-atmopshere system. In this way, sinking zooplankton fecal pellets can actually affect the global carbon cycle! I found this so incredible, that I became interested in studying zooplankton feces.

I hope this answers your question!!
~Karen S.

By: Steven Tuorto

Steven Tuorto — Fri, 06 Jun 2014 00:36:45 +0000

It turns out, there’s actually plenty of light below 200 meters! This includes light that comes from the surface, light from bioluminescent organisms, and other sources. As Jon (Cohen) has found in his work, it seems that even under extremely low light conditions, animals still have a clear visual response. Other researchers have shown that some animals use visual techniques even down to 1000 meters, and probably deeper.

-Justin

By: Steven Tuorto

Steven Tuorto — Fri, 06 Jun 2014 00:29:27 +0000

Not yet! However, it seems that just about any animal has some type of camouflage, even if it’s not as fancy as some others. Imagine what you might do if every time you went to the grocery store, you had to watch out for predators…or if you had to sneak up on the food before you bought it!

-Justin

By: Steven Tuorto

Steven Tuorto — Thu, 05 Jun 2014 23:23:49 +0000

The shells of plankton have been accumulating on the sea floor for thousands of years, in some places even millions of years. When we pull up a marine sediment core (a long tube of mud that extends from the sea floor down into deeper layers of sediment), that core contains material that provides clues to what the past ocean was like. One way to learn about past climate is to identify the shells of plankton that are present at each depth. The sediment layers are stacked on top of each other like pages in a book, with information on each page that is part of a continuous climate history. Identification of species in the sediment record can tell you a lot about past conditions: you only see palm trees in warm places, and in a similar way, some types of plankton are present only in tropical waters. Others live only in cold waters. By taking note of which types of plankton are abundant in a core, you can get an idea of how climate may have changed in the past. For example, in sediment that is 20 thousand years old, you’ll likely find more cold-loving species, because at that time, Earth was in the deep grip of an ice age. In addition to species identification, we can analyze the chemical composition of plankton shells to learn about the chemistry of the water in which they grew. This is a rapidly-advancing frontier: development of new tools and techniques for gleaning climate information from fossil shells on the sea floor.
–Kat Allen

By: Steven Tuorto

Steven Tuorto — Thu, 05 Jun 2014 22:19:16 +0000

Hi Isabel! There are a couple of reasons why so many of us study microorganisms rather than the larger organisms in the sea. For one thing, there are many, many more microbes in the ocean than there are fish or marine mammals or sharks. In just 1 liter (about a quart) of seawater, there may be 1 BILLION bacteria and archaea, and ten times as many viruses. Of course, bacteria and viruses are very small. But if you weighed all of the life in the ocean (what scientists refer to as the biomass), 95% of that weight would be microscopic life, and only 5% would be everything else- including really large animals like whales! Aside from being very abundant, microbes play extremely important roles in the ocean. They form the base of the food web, and many larger organisms rely on them as a food source. They also break down dead, decaying organic material and fecal material, in a process known as remineralization. This makes nutrients available so that more food can be produced. Microscopic phytoplankton in the sea are also responsible for producing half of all of the world’s oxygen- that’s every other breath you take! The chemical processes that microbes perform in the ocean effect marine life at every scale, in ways that we are still learning about. Understanding the microbes and the roles that they play helps us to understand how life in the sea works.
On top of all of that, scientists are fairly confident that life began in the ocean as single cells. When we study microbes in the ocean, we are really studying a very ancient form of life. In fact, many microbial oceanographers also study exobiology- the search for life on other planets. When scientists look for signs of life in space, they always look for one thing: water. And we are pretty sure that if we do find life on another planet, it will likely be microscopic. So, the more we understand about the limits of microbial life in the sea, the better equipped we will be to find life outside of Earth.
-from Lauren Seyler

By: Steven Tuorto

Steven Tuorto — Thu, 05 Jun 2014 21:29:12 +0000

As I’m finding out, there’s still plenty of light that makes its way from the sea surface down to very deep depths. Also, many predators bring their own light, in the form of bioluminescence, which is often used to search for prey. So, given that there are (at least) these two light sources present, it seems reasonable that animals would evolve to reflect or absorb light in useful ways.
-Justin

By: Steven Tuorto

Steven Tuorto — Thu, 05 Jun 2014 18:16:49 +0000

…An interesting question. Much of what we do is partially processed after we get back to land, which tells us if we really achieved our goals. But all of our sampling and operations are going very well. the plankton people are getting plenty of plankton, the chemists and microbiologist are getting the water, measurements and incubations they need done, and so this has been a very successful cruise so far. Visit our photos page to see some of the operations and organisms being spotted and collected.

Thanks,
Steve Tuorto

By: Ariana

Ariana — Thu, 05 Jun 2014 14:38:26 +0000

to Justin Haag, have you discovered any animals that you didn’t know that was camouflage?

By: Coleby from Morsepond school:)

Coleby from Morsepond school:) — Thu, 05 Jun 2014 14:34:41 +0000

How many pounds of food does the boat produce each day

By: Amelia from Morse pond school ;)

Amelia from Morse pond school ;) — Thu, 05 Jun 2014 14:33:00 +0000

I know most cave dwelling animals are blind because of the lack of light, why would it be different for ocean predators below 200 meters?