Examining Vertebrate Skulls

  

Next we will. introduce the idea of  Using Dichotomous Keys to help identify things. 

We will use this key to do a lab on identifying mammalian skulls.  Be careful with these skulls!  They are very fragile.  We will take two periods to complete this lab.

CLASS NOTES: 
STUDY QUESTIONS TODAY:


1.  What is meant by the word "Adaptation"?
2.  Skull adaptations for predators/prey include the placement of the eyes.  Explain why eye socket anatomy is different in predator vs prey.  Give examples
3.  What teeth do predators have compared to prey?
4.  How are the skulls HOMOLOGOUS TRAITS?  What is a homologous trait?
5.  What is an analogous trait?



IDENTIFICATION LAB:

Purpose:
1.  To identify a set of mammalian skulls and determine whether the animal is a predator or prey
2.  Demonstrate an ability to use a dichotomous key
3.  Draw each specimen and demonstrate your ability to observe using the skill of drawing.
4. Make conclusions about what animal this might be. 

For each specimen: 10 marks per specimen:
1.  Make a half page drawing where you measure and label parts     
5 marks - your color drawing is in ink, and  half a page and every part is labeled, and you have measured it in cm
3-4 marks, drawing is not in colour, it is in pencil, or less than half a page or some parts not labeled.  or you did not measure, or it is a rushed drawing
1-2 marks - it is incomplete

2.  observe the eye sockets and the teeth and conclude whether the skull belongs to a predator or prey
3 marks - you explain yourself very clearly and give your reasons and they seem logical
2 marks - your reasons are logical
1 - you are correct and need to provide more evidence for your point of view

3.  Take your best shot at identifying this specimen, give reasons for your conclusion.
2 marks - you are spot on!  or, if it is inconclusive, you give your best evidence for what it might be
1 mark- you are making a pretty good guess and you provide some evidence



Some useful information:

Dichotomous key for rodents
 Dichotomous Key for Mammals in the USA
Mammals of Alaska
The following quote is from
https://www.earthlife.net/mammals/teeth.html

"Teeth in mammals come in four different sorts: Incisors, Canines, Premolars and Molars. Not all mammals have all, or even any of them and the roles any particular sort of teeth play in an animal's life can be quite diverse. The arrangement of teeth in any given mammals mouth can be expressed as a 'dental formula'. This formula gives the arrangement of one side of an animal's jaw such that incisors are always written first then canines then premolars and then molars.

For humans 2123-2123 is upper and lower jaws respectively signifying 2 incisors, 1 canine, 2 premolars and 3 molars on each side in both the upper and lower jaw.

In total this adds up to 8 incisors, 4 canines, 8 premolars and 12 molars = 32 teeth in humans. Other mammals have different numbers of each sort of teeth in their upper and lower jaws. Hence Smoky Bats (family Furipteridae) have the dental formula 2123-3133 whilst Hyenas have 3141-3131 normally.

Incisors = Cutting teeth - these are the front most teeth in the jaw primarily used for the initial biting of food. They have a straight, sharp cutting edge and one root. In many Rodents they grow continually throughout the animals life, this is because they get warn down gnawing through things.

Canines = Stabbing teeth - normally only 2 pairs (one each side) per jaw. They have a sharp, pointed edge and are used with the incisors to bite into food and or to kill prey. Like incisors they have one root. The tusks of many animals such as elephants are modified canines. They are missing in rodents and most large herbivores (Perissodactyls and Artiodactyls). The gap where the canines would have been is often enlarged and is called a 'diastema'.

Premolars = Next back from the canines. They are generally similar to molars in form and function in both herbivores and omnivores, but in carnivores some of them at least are slimmer and are used to cut flesh. When they (the first lower premolar and last upper premolar) are modified like this they are called the carnassials. Otherwise premolars are teeth we use to crush and grind our food. Their upper surfaces have a broad, lumpy top instead of a sharp biting edge. These small irregular lumps are called cusps. Premolars are called bicuspids in some books, this is because, in most cases, they have two cusps. The prefix bi meaning two. The first upper premolars normally have two roots. The other premolars have one root.

Molars = These are larger than premolars and extremely variable depending on the animal's diet. Like premolars they are used for crushing and grinding food, and like premolars their upper surfaces have ridges called cusps on them. Molars normally have three to five cusps and two or three roots. In humans we call the third molars, those closest to the back of the mouth 'Wisdom Teeth'. If the jaw bone is not large enough to accommodate all the teeth in it, as sometimes happens with humans, these wisdom teeth can become painfully wedged between the back of the jaw bone and the 2nd molars. This condition is known as 'impacted wisdom teeth'."

Example:  Domestic Cat

Examine some specimens

 ...and classify them with as many taxons as you are able to. How did you arrive at your conclusion? Give some evidence for how you know you have correctly identified the organism.  You may work with others. Please clearly indicate which person completed which part of the assignment.  

Evaluation  /20

17-20. You not only identify the organisms, but you provide excellent, evidence based reasoning. Your project is written in pen or typed and you argue you points brilliantly

15-16 You correctly identify the organisms and you provide excellent reasoning, supporting your points with evidence

10-14 you correctly ID the organisms and you provide some evidence. Your work is a good start, needing a few edits

0-10 Your work is a good start. It is not complete.

Making a safety plan

Create a trip safety plan 

1.  Names of group members, including cell phone numbers and Emergency contact and their numbers

  Ensure consent forms are handed in 

2.  Name of group leader

3.  Draw a map of the destination 

4.  Make a detailed trip plan including the itinerary 

  a. how will you meet your group

  b. where will you meet

  c. timing 

  

5.  On your map of the destination colour code our route

6.  What hazards are to be found ?  how do we mitigate those hazards?

7.  What if a group member goes missing during our trip, what is your group response?

10 marks for a completed safety plan

Bushtit nest sample

 

FYI if you are working from home, I will upload clear pictures of the bushtit nest here on this blog and on TEAMS, so you may do this assignment.

Investigation:  Write a report as a  document or slide show. 

1.  a.  Here is some info on  Bushtit biology right here:  an excerpt from the website:

"Bushtits need to eat 80% of their body weight each day to keep up with their speedy metabolisms when weather is warm- they eat even more when it cools down. According to a study from 1907, bushtits in California had diets that consisted of 81% insect matter through most of the year, and which increased to 100% insect matter in the spring. "  

http://wildfarms.weebly.com/blog/bushtit-fluffy-insect-eating-swingers

write 10 points which characterize bushtit biology

1.  NEST SAMPLE (shared microscope) : Observe the tiny sample of the nest under the microscope and report what you see.  Can you see the spider silk?  The moss?  feathers?  Take a picture with your camera if you can.

2.  COLLECT YOUR OWN SAMPLE OF a similar species of MOSS and LICHEN  that is NOT from the nest  from outside and examine this magnified either under the microscope ( OR using your camera to take a really close shot )  and draw your sample.  Answer this question: What properties of moss make it suitable for nesting material? 

3.  Listen for the sound of a bushtit around our school.  Observe for bushtits over a few days.  Draw a map of where and when you hear this sound and include it in the report.   

The sound can be found in this video here

4.  Optional extra observations:  Some of you began looking at other interesting specimens in our class and using our microscopes.  If you looked at other specimens and photographed them, include them here too.  If you did not, no worries, number 5 is optional.

Evaluation

17-20 - This is a beautifully presented assignment with clear observations, photos, drawings and observations.  It is insightful and excellently done. It is typed or written in ink and in colour

13-16 - This assignment is complete and very well done with great photos and observations. It is in pencil

5- 12 - This is a good start with some good observations but it is incomplete

Eukaryotes and prokaryotes

How to focus a microscope

 

Make a prepared slide by adding a drop of water on the slide and then put a cover slip carefully on your specimen 

prepare the following specimens

 1. a piece of paper towel

2. bushtit nest

3. moss specimen

4. blade of grass

Make a drawing half page of each specimen. 

Dead or Alive

 Welcome to  Life Sciences (Biology) 11 

This course is a field course which will cover all the major phyla of life.  It is expected that you will receive most of your course content on line and we will do labs and field study in class.  You will hand in ALL assignments through Microsoft Teams.  Below are your first week of assignments.  

ASSIGNMENT 1. HAND IN YOUR CONSENT FORM  /5. It will give us the ability to walk to Trout Lake or Renfrew Ravine at any time that I announce during the term.   Bring this consent form to class.

evaluation:  5 points for handing this in

CREATIVE ASSIGNMENT 2:  DEAD OR ALIVE

For your first assignment, I would like you to go outside and find the following objects  Photograph them or draw them and write about them in a little paragraph of no more than a third of a page.  You may answer in the form of a type written response under your photo, OR you may write it out in hand writing and draw your answers. 

1.  Find something dead.  How do you know it is dead? 

2.  find something alive.  What is it about this object that makes it alive?

3.  Find something that has never, ever been alive.  What characteristics does this object have that tells you that it is neither dead nor alive. It is nonliving.

4. Find something that is not alive, but an important PART of something alive.  Explain your answer

5. Look at your responses and ask yourself:  What is the criteria of being alive?

evaluation : /20 points)

CREATIVE ASSIGNMENT 3. A SUMMARY OF BIOLOGY AND THE CELL

Read this. 

Review of the Cell:  Life, Death and Self Destruct Sequences

And watch this intro video on Eukaryotes and Prokaryotes

Welcome to my Class

 Welcome to  Life Sciences (Biology) 11 

This course is a field course which will cover all the major phyla of life.  It is expected that you will receive most of your course content on line and we will do labs and field study in class.  You will hand in ALL assignments through Microsoft Teams.  Below are your first week of assignments.  I have set up my class so that the majority of the class notes shall be distributed on line from this blog.  

The majority of class time will be lab work (examining skulls, bacteria, plants, microscope work) and also field study (walking to Trout Lake).  My windows shall be open ALL THE TIME to give us nice fresh air  so dress warmly! 

ASSIGNMENT 1. HAND IN YOUR CONSENT FORM  /5

I would like you to hand in a consent form. It will give us the ability to walk to Trout Lake or Renfrew Ravine or Patterson Station Central Park at any time that I announce during the term.   Bring this consent form to class.

evaluation:  5 points for handing this in

As we go into SEMESTER 1, I would like to prepare for learning during the FOURTH wave of Covid 19.  I would like to remind everyone that the best way to protect one another in class is to keep our distance (2m), wash our hand frequently AND to wear a mask. 

I invite you to flatten the curve by these simple measures! We will beat the delta variant of Covid 19 together!   Further, all of my class assignments will be posted here on this blog and therefore, if anyone misses any class due to illness, or self-isolation, you can easily keep up with the work. 

SAFETY MEASURES:

- physical distance, as much as  possible in our full classes.  Avoid being in each other's space.

- wear a mask! It is MANDATORY in the VSB!  (if you have medical reasons for not wearing a mask, please have your guardian inform me) 

- no academic penalties for being home sick, with any mild illness, isolating, or +ive with covid 19

- windows shall be open in my class to admit adequate ventilation AT ALL TIMES, even in the winter. Therefore, dress accordingly.

- we can conduct class outside sometimes to do field study