Lesson: Mammal Characteristics & Adaptations

Warm Ups, etc:

2 Questions, 1 Answer - students use photos in textbook and their own knowledge/curiosity to generate 2 questions and provide a fact about mammals #content #criticalthinking #community #collaboration #communication #creativity

The Mammal That... - students identify individual examples of mammals that meet certain criteria about lifestyle, diet, habits, etc. #content #criticalthinking #community

Mental Hairballs- review the formation, evolution and adaptive radiation of mammals #content #criticalthinking

Lecture Notes: #content

Notes – Mammals

You are a mammal and you have _________ and produce _____________ (hair / milk)

You first evolved in the Permian Period from mammal-like reptiles

Through the Mesozoic Era you remained small while dinosaurs dominated

65mya (called the K-T Boundary) the dinosaurs went extinct

Since then you have demonstrated rapid adaptive radiation

What has evolution given you?

1. Endothermy – The metabolism of nutrients and muscle movement maintain homeostasis by heating the body from within. The addition of insulating hair and subcutaneous fat allow nocturnal activity and survival in cold areas
2. Diverse dental and nutritional flexibility - Jaw strength and structure combined with a variety of tooth structures allows higher consumption and a broader range of available foods. Diets and GI structures alter as needed:

- herbivore – cutting incisors &grinding molars, multiple “stomachs,” long intestines

- carnivorous/scavenger – biting, tearing, piercing, cutting teeth, short intestines

- omnivores – a mix

1. Bronchial Aerobic Respiration – You must breathe air from the atmosphere into the lungs that operate due to ribcage and diaphragm muscles.
2. Four Chambered Heart – a closed double-loop keeps venous (CO₂) and arterial (O₂) blood separate. It also effectively moves materials and wastes and helps regulate temperature. (Only birds and crocodiles share this feature!)
3. Urine- Highly efficient kidneys balance salts and sugar levels in making a concentrated nitrogen waste. This allows life in a variety of harsh climates.
4. Cerebrum – Mammal brains are highly developed in the processing region, allowing advanced communication, thinking and learning. With this there has been a broad range of sensory adaptations (color vision, echolocation, smell…)
5. Skeletal flexibility – In 2 ways 1) Basic structure can be modified for a huge range of specialized functions 2) 4 limbed with a joint structure and backbone allow flexible motion
6. A Nourishing and Caring Mother – All mammals exhibit internal fertilization and most have live birth. Young are fed milk secretions from mammary glands and are often reared for a prolonged period

- Non-Placental - Monotremes (egg), Marsupial (pouch)

- Placental - womb

Objectives and Vocabulary: #content

Activities, Assignments, Etc.

Introduction – Weird Mammals – presentation of weird mammals to generate additional interest, riding off the student question driven discussion of WU 2Q/1A

Assignment “Mammal, Mammal” –

Part A-students use 26-1,30-1,33-1 to answer the following

1) What are the four key shared characteristics of animals?

2) Distinguish between invertebrates and vertebrates. Give the relative percentages of each.

3) Briefly explain/define the seven essential functions of animals.

4) What are the four characteristics of chordates?

5) How are vertebrates more specialized than nonvertebrate chordates?

6) Copy EITHER fig 33-2 or fig 33-4.

Part B-students use 32-1 to answer the following-

1) Define “mammal”

2) When did mammals first appear?

3) Describe the earliest mammals (as far as scientists hypothesize…)

4) What event led to the massive adaptive radiation of mammals 65mya, in the early Cenozoic?

5) Starting with “Form and Function in Mammals” on 822 – create an outline/summary that explains the importance of each development (Body Temp/Feeding/…) in making mammals so successful today

Closure Assignment: (also introduces next lesson)

Closure – They MightBe Giants – “Mammal, Mammal”