Agenda

Birds and Juvenile Dinosaurs

EXTRA LEARNING: Great job again on the presentations today, especially the Reptiles group who got the audience so engaged that they kept asking questions! Also great job to Scott for presenting the multiple views about the relationship between birds and dinosaurs. Scientists are indeed still debating about this particular relationship. Some think that birds evolved directly from one lineage of dinosaurs. Others think that birds and dinosaurs shared a common ancestor. Here is another more recent hypothesis published in Scientific American (based on a paper in the science journal Nature) proposing that birds were originally juvenile dinosaurs: "Did Retained Juvenile Traits Help Birds Outlive Dinosaurs?" The debate goes on as scientists discover new fossils and new lines of evidence. 

Coelacanth

EXTRA LEARNING: Since today's presentations were about fishes and amphibians, I thought I'd share the following documentaries about coelacanths, a "living fossil" that provides a link between fishes and tetrapods. This is the video clip I showed in class: "Finding the Coelocanth" from National Geographic Wild. Here is a longer documentary about the history of scientists' search for these creatures: "Coelacanth: The Fish that Time Forgot." One of my students asked about how these creatures lived and reproduced. What scientists know is that the coelacanth is ovoviviparous (recall what that means) because they have found dead specimen that carried live young within their bodies. The young had yolk sacs attached. These fish are thought to have one of the longest gestation periods among vertebrates--from one to three years! Some neat features that illustrate how ancient these creatures are can be seen in their lobed fins (with arm-like bones!), their hollow notochords, and the peculiar way in which they swim. These fish do not have a backbone at all, but rather a more primitive feature: a hollow notochord. Additionally, their swimming pattern is similar to how tetrapods walk; more accurately speaking, tetrapods evolved their walking pattern from ancient ancestors similar to the coelacanth. The next time you're walking about, notice how your arms and legs move: left leg and right arm move together and right leg and left arm move together. Creatures like the coelacanth were the first to develop that pattern of motion.

Other interesting things related to fishes and amphibians: mudskippers, flying fish, flying rays, axolotl, new species of caecilians, fish vs. fishes.

Prehistoric Insects and Birds

EXTRA LEARNING: Since one of today's presentations was about arthropods, I thought I'd share this recent article published in National Geographic (originally based on a paper in the Proceedings of the National Academy of Sciences). Previously, scientists had linked insect size to fluctuations in oxygen levels in the atmosphere of prehistoric Earth. Recall how insects respire. Higher oxygen levels would thus allow them to evolve larger bodies. Recent studies by researchers at UC Santa Cruz, however, propose a different story. According to them, insect size decreased due to predation from birds which were showing up on the evolutionary scene. Small insects were more maneuverable than large insects, thus conferring small insects an advantage. These researchers note that after the appearance of birds, even during periods of higher oxygen levels, insect size remained small. Interesting. Read more about it if you like: "Giant Bugs Eaten Out of Existence by First Birds?"

Also interesting: carnivorous caterpillars on Hawaii. Similar video clip.

Animal Presentations this Week

This week is devoted almost entirely to your Animal Kingdom Presentations! Remember to carefully observe your classmates' presentations both for the Animal Kingdom Test on the last day of school as well as for ideas on how to improve your own presentations. Also check the "Lecture" tabs for the PowerPoint slides from these presentations. On Thursday and Friday, we will have block schedule (of ~2 hours per period) to accommodate senior finals. Sixth period will meet on Thursday and seventh period will meet on Friday.

For your notebook for this unit, you have two-ish options: (1) recopy notes as you've been doing for the other units or (2) write down two pages (or two sides of one page, depending on how you see it) of thinking. This thinking can be in the form of a summary of the presentations, an organized comparison of the different animal phyla, or responses to the review questions after each section on animals in your textbook. When I check your notebook, I will be looking for two pages of work per presentation. I suggest you make the presentation topics stand out. For example, if your notes are on mollusks, then highlight "mollusks" or write "mollusks" in huge letters, followed by two pages of work on this group of animals. Then repeat for each presentation. Colored drawings/diagrams earn extra credit, as do highlighting and underlining.

Finally, I've created a Kingdom Animalia Study Guide for your test on June 14th. You may use this study guide on the test, so I suggest you take good notes. The notes must be handwritten (not typed), and yes, you may write the responses on a separate sheet of paper. The study guide is not an assignment, so I will not be collecting it. It is mostly to guide you on what to study for the test.

EXTRA LEARNING: For those who are interested in how to form the plural of "octopus," here is an explanation from one of the editors of the Merriam-Webster Dictionary: octopuses vs. octopi.

Good Job Today!

Good job today, presenters! The PowerPoint slides for the presentations today have been posted on the class website under "Lectures." (Note to seventh period: Since the cnidarian group did not complete the assignment, you may use the PowerPoint from sixth period to study.) Make sure you pay attention to your classmates' presentations. You will have a test on the Animal Kingdom on the last day of class. 

The groups responsible for Worms and Mollusks will present next Monday. Tomorrow, we will watch a documentary on cnidarians as an introduction to the hydra lab you'll be doing on Friday.

The Shape of Life

EXTRA LEARNING: There is this very neat documentary series on PBS called "The Shape of Life" that traces the origins of animal evolution. What's especially useful about this series is that they divide their episodes into the categories of animals that you are presenting! The entire series is on YouTube for those who are interested. Remember, we start presentations tomorrow. =)

Sponges: "Origins"

Cnidarians: "Life on the Move"

Planarians: "The First Hunter"

Annelids: "Explosion of Life"

Mollusks: "Survival Game"
Arthropods: "The Conquerors"

Echinoderms: "Ultimate Animal"

Vertebrates: "Bones, Brawn and Brains"

Notebook Check #13 due Tuesday

Good job on the Plant Unit Quiz today. Your two last assignments for this unit are the Plant Organs lab report and the Notebook Check #13. The grading sheet has been posted under "Documents." Don't forget the parent signature. Both of these assignments are due next Tuesday.

*** Remember to add Question #5 to your lab "Data Analysis" section: 5. Based on your knowledge of monocots and dicots, was the lily you observed a monocot plant or a dicot plant? What characteristics did you rely on to determine your answer? ***

We will start the Animal Unit next week. On Tuesday, you will have time to work on your projects at school. Remember to meet in the computer lab in the library. Bring your own laptop if you like. Then starting on Wednesday, you will watch presentations by your classmates. I revised the rubric for the animal presentations. You may look at it (under "Documents") to see how I will grade you. 

Lastly, remember that there is a slight change in the schedule next week. Because the hydra you will be observing in lab won't be ready until next Friday, we will need to switch the agendas for Thursday and Friday. On Thursday, the groups responsible for Worms and Mollusks will do their presentations. Then on Friday, we will do the hydra (cnidarian) lab. Those of you who will be going on a field trip next Friday will need to make alternative arrangements. For example, you may ask your lab partner to perform the lab in class, then you write the lab report afterward. Or, you may come to school early on Friday (before the field trip) to do it. I can keep the hydra over the weekend until Monday morning, but I doubt most will still be alive by then. You can hope that they'll still be alive for you to observe them then. If you cannot make arrangements to somehow complete the lab, then you will need to write a 3-page essay about cnidarians as the make-up assignment.

EXTRA LEARNING: In class, we learned one of the reasons why commercially ripened tomatoes don't taste as good as naturally ripened tomatoes. It has to do with chemicals, or lack thereof. Here is an article exploring that issue even further: The Science of Tasty Tomatoes. This article is also interesting; it relates genetic engineering to enhancing tomato flavor: "Genome could enhance tomato taste."

Plant Quiz on Friday

Your quiz on plants is on Friday. Review your notes, the lab, and the textbook for clarification. And ask questions if you have any. The Plant Unit PowerPoint slides have been posted under "Lectures." I also created a study guide (under "Documents") for your Plant Quiz. If you know the answers to the topics on the study guide, you should be able to ace this quiz. For one point of extra credit, you may also post a multiple choice review question with at least four answer choices. The extra credit is due by Friday. Your plant lab report is due next Tuesday. =)

Print Out Plant Lab

Print out the Plant Lab sheet and bring it to class tomorrow, Wednesday. If we have time after the lecture, I will stamp your lab sheets and go over the lab with you. If we don't have time, then I'll go over the lab before you do it on Thursday.

Also, remember that you may bring in plant samples either Wednesday or Thursday for extra credit. See the post below for more information.

Extra Credit: Bring in Plant Samples

Since we are learning about plants this week, I am offering the following extra credit opportunity: You may bring in a plant sample to share with your classmates. Some examples of plant structures you can bring in are roots, stems, leaves, flowers, fruits, pinecones, etc. Suggestions of where to look are your backyard or garden, nearby places that have plants (e.g., parks, hiking trails), or your grocery store. You will earn 1 point of extra credit toward your test grade for bringing in a common plant or plant structure. You will earn 3 points of extra credit for bringing in a rare plant or plant structure, such as a Venus' flytrap or gingko biloba leaves. You do not need to talk about what you brought in (but you may if you choose). We will basically pass them around so your classmates can see "live samples" of plants and plant organs. =)

Notebook Check #12 Tomorrow

Remember that your Notebook Check #12 is tomorrow, Friday. Don't forget your parent signature. Also, the Reproductive Systems PowerPoint slides have been posted online under "Lectures." =)

Notebook Check on Friday

Today, I distributed the assignment sheet for your Kingdom Animalia Project. I am giving you this assignment now so you can have plenty of time to work on it. The first presentation is not scheduled until May 30th, which is more than a week away. On May 29th, you will be given a day to work on the project at school; we will meet in the computer lab in the library. Other than that, you are expected to complete the project with your group members outside of class. Be informative but also creative. This is your chance to teach the class. =)

Secondly, your Notebook Check #12 is due on Friday. To encourage you to complete as much of the notebook as possible (in order to get the maximum amount of credit) I am requiring you to have your parents check your notebooks for completion. I will not accept a notebook that does not have a parent signature. If you forget a parent signature, but still bring the notebook on Friday, then I will ask that you have your parent sign it when he/she picks you up from school and submit it before the end of the school day.

CST Testing This Week

You have CST testing Mondays through Thursday this week. We will cover the Reproductive System this week as well. Sixth period will meet on Monday and Wednesday, and seventh period will meet on Tuesday and Thursday. Remember that your Reproductive System worksheet is due on Wednesday for sixth period and on Thursday for seventh period. On Friday, we will watch a documentary about the reproductive system.