Chapter 33
Mammals

Mammals are endothermic animals, which means they are able to generate substantial body heat internally.
http://www.exploringnature.org/graphics/Mammals_K2_72.jpg

Most species are experts at maintaining a constant body temperature. They have combinations of fur, hair, and subcutaneous fat and sweat glands http://media1.shmoop.com/images/biology/biobook_animalmovement_graphik_53.png

Young mammals develop within the mother for a time and then are born alive

http://img.tfd.com/vet/thumbs/gr258.jpg
Mammary glands

A diaphragm and the fourchambered heart http://blogs.nejm.org/now/wp-content/uploads/2012/03/Dysfunction-of-the-Diaphragm.jpg
http://rbssanimalsystems4.wikispaces.com/file/view/heart_with_labels.jpg/291104367/heart_with_labels.jpg

The first mammals were small and resembled tree shrews. They were nocturnal out at night.
http://tomduhamel.files.wordpress.com/2013/01/megazostrodon.jpg

Three groups of mammals http://facultylounge.whfreeman.com/files/images/figure_11_15_03.preview.jpg
http://facultylounge.whfreeman.com/files/images/figure_11_15_02.preview.jpg
http://facultylounge.whfreeman.com/files/images/figure_11_15_01.preview.jpg

Three types of teeth: Incisors,
Canines & Molars http://www.studyblue.com/notes/note/n/topics-dentition-evolution-of-body-reproduction/deck/1131624

Carnivore Vs. Herbivore teeth http://collections.burkemuseum.org/mtm/mam_skulls.php

Rumen-chamber in the digestive tract that contains bacteria that produce enzymes which aid in breaking down cellulose http://ag.ansc.purdue.edu/sheep/ansc442/semprojs/2003/feedlamb/mag1.htm

Food gets regurgitated as cud and chewed again https://twitter.com/AtlantaCud

Cecum- sac that aids in digestion similar to a rumen http://www.dicts.info/picture-dictionary.php?w=cecum

Respiratory muscles: chest muscles and diaphragm http://concept2.co.uk/training/breathing

Circulatory system transports gases and nutrients to the rest of the body http://www.elateafrica.org/elate/biology/transportanimals/transportinanimalsintro.html

Kidneys are the most highly developed of all invertebrates http://open.jorum.ac.uk/xmlui/bitstream/handle/123456789/947/Items/S324_1_section8.html

Kidneys extract N from blood and form urea. Also excrete and retain liquid http://www.arizonatransplant.com/healthtopics/index.html

The mammalian brain is more highly developed than any other animal’s brain http://thebrain.mcgill.ca/flash/i/i_05/i_05_cr/i_05_cr_her/i_05_cr_her.html

3 main parts of brain: cerebrum (thinking and learning), cerebellum (coordinates movement like flight), medulla (regulates body functions like breathing and heart rate) http://www.myschoolhouse.com/courses/O/1/34.asp

Three senses of mammals: Sight,
Hearing, and smell https://www.dana.org/news/brainhealth/detail.aspx?id=10064

Protection behaviors (horns and hooves or just running) http://www.mining.com/bondholders-heading-to-gold-since-they-have-no-where-left-to-run-sprott-66084/

Herbivore defense

Mammal movement: running, climbing, flying, and swimming
(homologous structures) http://mudfooted.com/platypus-mammal-eggs-bill/ http://www.earthweek.com/2009/ew090123/ew090123f.html
http://www.bbc.co.uk/nature/adaptations/Climbing

Biologists link mammals to reptilians by the ability of some mammals to lay eggs (monotremes) http://www.sciencedirect.com/science/article/pii/S1084952112000699

Yolk Sac-nourishes the developing embryo inside the marsupial’s reproductive tract http://9e.devbio.com/article.php?id=108

Marsupium-pouch on the mother where the baby goes and nurses for several months http://www.whereincity.com/india-kids/animals/kangaroo.htm

Placenta-organ through which nutrients, oxygen, carbon dioxide, and wastes are exchanged between embryo and mother http://www.nlm.nih.gov/medlineplus/ency/imagepages/17010.htm

Advantages of having placenta
• 1. Allows the embryo to develop for a much longer time inside the mother
• 2. The mother is able to feed and still protect the developing embryo

Gestation period-the time the embryo is developing in the uterus

Long learning period and prolonged childhood give mammals success http://www.africas-eden.com/Wildlife-of-Gabon.asp

Monotremes http://www.ucmp.berkeley.edu/mammal/monotreme/echidna2.jpg

Marsupials http://visual.merriam-webster.com/images/animal-kingdom/marsupial-mammals/examples-marsupials.jpg

Placentals http://www.evolution-textbook.org/content/free/figures/22_EVOW_Art/07_EVOW_CH22.jpg

Insectivora http://www.codigovenezuela.com/sistema/wp-content/gallery/topo/star_nosed_mole-s1360x673-2274.jpg

Chiroptera http://images.nationalgeographic.com/wpf/media-live/photos/000/005/cache/common-vampire-bat_505_600x450.jpg

http://tolweb.org/tree/ToLimages/armadillo.jpg
Edentata

Rodentia

Lagomorpha http://ichef.bbci.co.uk/naturelibrary/images/ic/credit/640x395/l/la/lagomorpha/lagomorpha_1.jpg

Carnivora http://upload.wikimedia.org/wikipedia/commons/thumb/a/a4/Order_Carnivora.jpg/250px-Order_Carnivora.jpg

http://upload.wikimedia.org/wikipedia/commons/9/9a/Cetacea.jpg
Cetacea

http://www.angelfire.com/mo2/animals1/images/manatee.jpg
Sirenia

Artiodactyla (even-toed ungulates) http://www.ultimateungulate.com/Images/artiodactyla.gif

Perissodactyla (odd-toed ungulates) http://www.ultimateungulate.com/Images/perissodactyla.gif

Proboscidea http://ichef.bbci.co.uk/naturelibrary/images/ic/credit/640x395/p/pr/proboscidea/proboscidea_1.jpg

Primates http://3.bp.blogspot.com/_DFeL3hEaCfQ/TTzwc_GeAII/AAAAAAAAABw/p74sCIj8LVo/s1600/DSC_4638.jpg