Friday, February 26, 2016
Thursday, February 25, 2016
We also discussed sea grass beds. Sea grass is super-important for stabilizing the substrate and holding the sand down. This promotes water clarity and decreases turbidity. Nothing eats sea grass when it is alive except for manatees. Everything else eats it after the bacteria have decomposed it a bit.
Photic vs Aphotic is an odd one involving the light and dark zones of the ocean. Some organisms hide in teh dark aphotic zone during the day and migrate up to the surface (the photic zone) at night to eat the phytoplankton. Predators also migrate to eat the things that are eating the phytoplankton.
Wednesday, February 24, 2016
One of the weirdest, but also most interesting is Whalefall. Whalefall is when a dead whale settles to the bottom of the ocean and organisms move in to feed on the carcass until even the bones are decomposed. Hagfish are a dominant scavenger as well as bacteria. It may not seem like a big deal, but this biome boasts over 160 species that are not found on the surrounding benthos. More info can be found at the link above, or here. Listen to a podcast here.
Deep sea benthos is another biome and it is pretty boring. Its a gooey squishy substrate populated by some dd scavengers, but there is not a high biodiversity and not a lot of food to eat.
Not all biomes are found at the bottom of the sea. Along coasts you can find rocky coasts, sandy beaches, salt marshes, mangroves, sea grass beds, kelp forests, and fouling communities.
I think fouling communities are really interesting... because all these organisms need is a hard substrate (surface) to stick on. This could be a dock, a pier, a boat, or anything that's in the water long enough. Most people have seen all the 'stuff' growing on the pole legs of piers and docks, but don't really think of the variety of organisms that grow there - or their importance. Most of these organisms are filter feeders and do a lot for water quality. They also break down the surfaces like scavengers... not something we want for our boats and docks we use, but important nonetheless.
There is a lot of information to learn this unit. Students will be given two review sheets - one general, one biome specific. The Unit 3 Test is one of the hardest of the year, and it will be soon.
Tuesday, February 23, 2016
Students identified zones on rocky coast pictures and took notes on the material. Here is an example of a photo where the zones can clearly be seen by changes in dominant seaweeds. The yellow layer is the upper zone and the white pink is the middle zone. It is easy to see the high water mark or where the high tide will reach. You can also see the lichens in the spray zone.
The spray zone is one of the hardest areas to live in because of the huge changes in salinity and temperature.
We also talked about tide pools. Tide pools are depressions that trap water when the tide recedes. You can find all kinds of things in tide pools, but tide pools in the lower zone have a higher biodiversity than tidepools found in the upper zone. This is because they are more often "refreshed" with water that keeps salinity, dissolved oxygen, and the temperature stable, as well as add nutrients and more food! Here is a neat article from National Geographic about tidepools (and where this photo is from).
Monday, February 22, 2016
There is also cyanobacteria - or the blue green algae which we discussed during the plankton part of the unit.
Some algae is calcareous - meaning it stores calcium carbonate in its tissues. This makes it crunchy and deters herbivores. The most common is a calcareous red algae that makes a pink crust on just about everything left in the ocean.
A lot of seaweed has air bladders to help it float towards the surface. Air bladders ensure adequate sunlight for photosynthesis. Other important adaptations include flexibility and gels to stay hydrated when the tide goes out. Students observed samples of dried seaweed.
Wednesday, February 17, 2016
Today students got new seats and started a new unit on Plants, Plankton, and Biomes. This is probably our longest and most difficult unit because of the large amount of information that needs to be learned and applied.
We started class with a discussion about phytoplankton (cyanobacteria pictured above) and its importance to the ocean and to the world. Phytoplankton are responsible for feeding most of the creatures that live away from the shore and they are important for adding oxygen both to the water and to the atmosphere.
We are learning about plankton! Plankton include organisms that drift through the seas that cannot swim and do not attach to the bottom. Plankton can be classified a variety of ways.
The first way is to classify them by size. Microplankton and nannoplankton require a microscope if you want to see them because they are so tiny. Macroplankton are small, but you can see them without a microscope. Megaplankton are big enough to pick up and include things like jellies.
Another easy way to classify plankton is into plants and animals. Phytoplankton are tiny plants that photosynthesize and make their own food. Zooplankton (belong in the the zoo) and are animal plankton.
This is my favorite website about plankton and it is where all my photos come from. Check out the other types of meroplankton.
Students have drawn their own plankton, tried to match meroplankton to the adult forms, and are currently designing plankton to compete in the Plankton Grand Prix - where the object is to sink slowly.
Wednesday, February 10, 2016
You can watch a video about the candiru fish in the Amazon that swims into other fish's gills and sucks their blood - not so bad - except urine smells the same, so when people are in the water peeing, it is attracted to the people and swims up their urethras. Ouch.
Mutualism is the relationship that is best understood because both organisms benefit - although the advantages are not often clear to us. Pictured to the left are an alligator and plover, eel and cleaner shrimp, and zebra and finch - all of these are cleaning relationships. The smaller organism eats parasites and gets a meal and the larger organisms will not eat it as well as get the benefit of being cleaner (less infection and disease). The bottom right picture is a blind bulldozer shrimp and a goby fish. They share a dwelling that the shrimp builds, and the fish lets the shrimp know when trouble is coming.
Parasitism involves things that give us the heebie jeebies. These parasites take advantage of their host, usually feeding on the host, and benefit. The host gets no benefits and over the long term is harmed. Pets can get a lot of different kinds of parasites. Some are internal and some are external.
Commensalism is when one organism benefits and the other is unaffected. So one gets all these advantages from the other... but the other doesn't get a benefit from it and isn't harmed by it.These pilotfish are always with the shark using him as a predator deterrent, but the shark never eats them and doesn't benefit from them in anyway.
Tuesday, February 9, 2016
When the sea otters are removed (like when they used to be hunted for their fur), the sea urchin populations go crazy, eat all the kelp (as in many many 300 foot tall plants), and the loss of kelp leads to a drop in biodiversity because there is less food and habitat for the many other species that like to live in and on and among the kelp.
Saturday, February 6, 2016
Parrotfish are part of the nekton because they swim. They are omnivores because they eat coral (animal) and algae (plants). This fish is a male because it is more colorful than its female counterpart. Some may consider this warning coloration because it will chomp on things that try to mess with it.
An odd part of their niche is that the coral they digest is where most of the white sand in tropical locations comes from.
Friday, February 5, 2016
In the animal kingdom, males are typically brighter and more colorful. The males are trying to prove to the ladies that they have good genes, they are disease free, and they can escape predators.
Larger males can win contests against other males also proving their good genes. Though the males show off, it is the female's choice when she ultimately makes a decision. It is possible for a female to reject all males and choose none.
Differences in size and coloration indicate that there is female choice, the female will choose a male to fertilize her eggs and in most cases, his job is done, and she leaves to finish the baby-forming process. All she wanted was his genes.
When a large group of organisms all spawn at the same time, the organisms rely on luck and statistical chance for genetic variation. Males and females will look similar because there is no choice involved.
When males and females work together and take an equal role in raising young or protecting eggs, the males and females tend to look more similar. They look similar because of their equal roles and because the choice is longer-lasting. She is looking for more than just a pretty face (and pretty faces in the animal world do not indicate good egg care or being able to provide nesting materials, food, etc).
Differences in size between males and females varies widely. There is no set rule for who will be bigger, but there is usually a clear reason as to why one of them is bigger. Males can be bigger because they fight other males, because they have to guard eggs, or other reasons. Females can be bigger because they have to carry and nourish a fetus, carry and develop eggs, protect babies, or other reasons. To know why a male is bigger or a female is bigger the biology and reproductive strategies have to be understood.
Thursday, February 4, 2016
Wednesday, February 3, 2016
After discussing bioluminescence (organisms that can produce their own light) we looked at a TED talk by David Gallo . Gallo's talk showed the organisms in accurate color and in motion. His talk also showed some amazing footage of cephalopods like cuttlefish and octopus performing magical feats of mimicry and camouflage. You should definitely follow the link and watch this video stream.
His talk was based on research by Dr. Widder. We looked at some of her photos and you can learn more about her work and see her presentation here.
When it comes to deep sea creatures - some bioluminesce and some don't. People are fascinated with the gulper eel, a four foot long eel that has a HUGE jaw. It has such a big mouth so that it can eat anything it comes in contact with because in the deep ocean, meals may be far and few between. More information about the gulper eel and other deep sea creatures can be found at Sea & Sky's Website.
You can watch a this one found on YouTube. This creature to the right is a Firefly Squid; it has amazing lighting capabilities.
For more information check out
The Bioluminescence Web Page
How Stuff Works
Or Sea and Sky's page about Bioluminescence.
Tuesday, February 2, 2016
Typically humans are getting taller and have bigger feet than their parents and grandparents. We think this is because of better nutrition.
We talked about the fossil record and how evidence shows whales changing from land mammals to sea mammals over millions of years and how you can observe the small changes in skeletal structure changing over time.
Monday, February 1, 2016
Computer Lab Etiquette
You are in the computer lab to do work for this class. If you are not doing work, then we will have problems.
Do not pack up early. Work until the bell or until MsJ says.
SAVE OFTEN. And if you save to a key, also save it to your number. If you lose it, you will have to do it again.
If MsJ asks for your attention, stop what you are doing and listen to what she has to say.
You may watch videos about your organism through reliable websites.
You may listen to music through the computer if you have your own headphones. Rule1 MsJ cannot hear it. You get one warning. Rule2 Turn it on and listen – no million clicks and constant changing. Take both ear phones out when MsJ is talking.