skull lab

 

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?


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.  note that one of the specimens does not clearly fit the key exactly. Just try your best to identify it. 

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

Feather Adaptations

  1.  Examine the bird wing .  Label the feathers on the bird wing specimen 

2.  Choose 3  feathers from the feather collection and see if you can identify it using the US Fish And Wildlife Feather Atlas     Draw the feather sand write down why you think it is this type of feather 

3.  Draw the Robin specimen and write about the habitat and feeding habits of the robin

4.  Draw the mallard specimen and write about the habitat and feeding habits of the mallard

5.  Read the following resource and answer questions about feathers  

Bird Academy 

a.  What is a pennaceous feather?

b.  explain the term plulumaceous

c.  What are the seven broad category of feathers.  Draw these.

d.  How do you know you are looking at a wing feather?

e.  How do you know you are looking at a tail feather?

the Genetic Code

 

NOTES: a summary of what we learned about protein synthesis

A diagram worksheet summary


More practice generating mRNA, tRNA and Amino Acids in this link here

how evolutionary change occurs

  WRITE A SUMMARY OF HOW SPECIATION OCCURS, WITH ILLUSTRATIONS.

 review these intro notes on evolution,  and read the notes on

How evolutionary change occurs

Review THE BIRD video on the steps of speciation and take notes on this, outlining the steps. 
2.  NEXT, write a summary of the human evolution video
https://www.nationalgeographic.org/video/human-origin-101/

Evolution Introduction

 Take a look at the Evolution power point and do the lab exercise at the end:

Evolution powerpoint

BIRD NEST lab

  

This bushtit nest is extremely fragile. It was collected from a Vancouver sidewalk more than 5 years ago prior to the outbreak of  the current mammalian variant of highly pathogenic avian flu.  Also Flu viruses are not viable for the time that has elapsed.  It is not advisable at this time to collect any bird nests due to potential exposure to HPAI.  

Do not take it out of its container.  Instead, use the petri dishes which contain parts of this nest to answer the questions.  

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.   

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 4 is optional.

Evaluation GROUP ACTIVITY 

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

NOTES ON CLASSIFICATION

 Read these notes on classification

please correct the following in these notes:   the notes show the old classification. today the new classification is:

Kingdoms archaea , bacteria  (formerly monera ) and eukarya 

and under the eukarya kingdoms kingdom animalia, fungi and plantae 

Answer these questions 

1.  What is classification?  Who invented it?
2. Explain the term binomial nomenclature
3.  What are the taxons of life, in order of largest to smallest?
4.  Define species.
5.  Cell respiration is a universal energy equation.  Where does it happen?  Write the equation.
6.  What is ATP, ADP.  Give an analogy for how this works
7.  Define Heterotroph and Autotroph
8.   ACCORDING TO THESE NOTES, What is the definition of
a. Animal
b. plant
c. Fungus
d. Protozoa
e. Monera