STATE SCIENCE STANDARDS: 6 th, 7 th, and 8 th Grade Skills and Processes: 1.0 D.3 Analyze the value and the limita ons of different types of models in explaining real things and processes. 6th Grade Science: 3.0.D. 1.a 3.0.D.1.c 3.0.D.1.d 3.0.D.1.e 7th Grade Science: 3.0.A.1 8th Grade Science: 3.0.D. 1.a 3.0.D. 1.b 3.0.D. 1.c 3.0.D.1.d Cite examples and describe that small differences between parents and offspring can accumulate (through selec ve breeding) in successive genera ons so that descendants are very different from ancestors. Explain that in any par cular environment individual organisms with certain traits are more likely than others to survive and have offspring. Explain, with examples, ways that people control some characteris cs of plants and animals they raise by selec ve breeding. Describe ways in which changes in environmental condi ons can affect the survival of individual organisms and en re species. Compile evidence to verify the claim of biologists that features of organisms connect or differen ate them these include external and internal structures (features) and processes. Recognize and describe that gradual (clima c) and sudden (floods and fires) changes in environmental condi ons affect the survival of organisms and popula ons. Recognize that adapta ons may include varia ons in structures, behaviors, or physiology, such as spiny leaves on a cactus, birdcalls, and an bio c resistant bacteria. Recognize and describe that adapta on and specia on involve the selec on of natural varia ons in a popula on. Recognize and describe that ex nc on occurs when the adap ve traits of a popula on do not support its survival. GOAL STATEMENT: Students will learn the role of horses in Maryland agriculture and come to appreciate the horse as a specific biological model.
OBJECTIVES: Students will learn about the evolu on of the horse over me and how the uses of horses have changed. Students will compare/contrast traits of horses used for different purposes. Students will learn terminology related to the horse industry. REQUIRED MATERIALS: Copies of Where Did the Horse Come From? clue cards (1 set per class) Horse Evolu on Timeline poster LEGO Kit 6177 Copies of LEGO Horse Examples handout (1 per group) AMOUNT OF TIME TO ALLOW: 60 75 minutes. Extension ac vi es will take addi onal me.
Evolu on of the horse dates back to approximately 56 million years ago. Since then, differences in height, diet, and anatomy have dis nguished the modern day horse from its ancestors. Interes ngly, the first horse only stood about 12 inches tall and walked on 4 toes in the front with 3 in the back. Eohippus, also known as the dawn horse, looked nothing like the modern horse. He was about a foot tall, stood on 4 toes, had a short face and a short neck, and grazed on berries, fruit and other plants. Changing environmental pressures such as changes in climate, disease/parasite epidemics, and compeon for food in conjunc on with natural selec on contributed to the evolu on of the horse. We recognize several dis nct ancestors of the modern horse based on certain traits and characteris cs (as described in the Background Informa on Teacher Key ). Mesohippus, also known as the middle horse, succeeded Eohippus. This animal was twice the size of Eohippus, standing at about 24 inches tall. It walked on 3 toes and had a longer neck and face along with a longer, fla er back. Instead of berries and fruit, it ate foliage and plants. As more changes occurred, Mesohippus was replaced by Pliohippus, also referred to as the More Horse. Pliohippus was about 50 inches tall and walked on one single hoof, much like today s horse. With a long, muscular neck and a longer face, it much more closely resembled the modern horse. The diet of Pliohippus was also similar to that od today s horse as Pliohippus mainly grazed on forages of the plains. The final chapter in equine evolu on is Equus, or the modern horse. On average, Equus stands about 53 inches; walks on a single hoof; and has long, powerful limbs and a long, slender neck and face. For a graphical representa on of this informa on, see Evolu on of the Horse: Background Informa on and Teacher Key included with this lesson. The history of the horse dates back 56 million years ago when its ancestors existed on the con nent of North America. Since then, horses have been domes cated and trained to serve a variety of purposes. Originally, the horse was thought of as a source of food. As mes changed, so did the horse s purpose. Horses became valuable as farm workers by plowing the fields, hauling wagons, etc. They also became a form of transporta on by pulling wagons and stagecoaches, moving supplies as well as people. In addi on, humans used horses as war mounts in cavalry divisions. The use of the horse changed again due mainly to the industrial revolu on and technology. Hand plows were replaced by tractors and other mechanized farm machinery. In terms of transporta on, horses were replaced by planes, trains, and automobiles. In Maryland today, recrea on is the largest use for equines, followed closely by showing and compeon. Racing is also a popular use for horses in the state of Maryland. With domes ca on came the emergence of different kinds of horses bred for different purposes. For example, a heavier boned, larger framed horse was developed with the inten on of li ing and pulling heavy carts and to be used as an all around farm horse. Today, these horses are referred to as dra horses. Dra horses are built for pulling heavier loads and some mes work in teams. These horses are very tall, ranging from 16.0 to 19.0 hands, and some mes even taller. Dra horses are sturdy horses, possessing substan al muscling and bone through their legs and body. A lighter framed horse developed with the inten on of speed, agility, and endurance resulted in the evolu on of what is called the light horse. Light horses are generally more spirited, finer bodied
animals that are used for riding. Their typically long legs and lean bodies make them ideal for sports like racing and jumping. Each category or class of horses is comprised by horses of specific breeds. A breed is a group of animals that descend from a common lineage and share similar characteris cs. For example, Shires and Percherons are two of many breeds of dra horses. If you have watched the Kentucky Derby, the Preakness, or the Breeder s Cup, you have witnessed Thoroughbred racing, one use of the light horse. The Thoroughbred breeds was developed in the 17 th century to run very fast. The Quarter Horse is another breed of light horse and is also the most popular horse breed in the United States. Quarter Horses are used for a variety of purposes including ranch work, showing, and pulling carts. Another light horse breed is the Arabian; Arabians are most well known for their endurance. 20 minutes Begin by asking students to very briefly share some of their experiences with horses. You may ask if any students own horses or if any have ever ridden a horse. Inform students that the first part of the lesson will consider where horses came from in an evolu onary sense. Lead a class discussion about evolu on to review what students already know. You may want to ask ques ons such as: What is evolu on? What causes evolu on? What is an adapta on? What is natural selec on? Help the class to understand that evolu on is the accumula on of small changes to an organism that occur over me as a result of changing environmental pressures and natural selec on. You may want to supplement students' previous knowledge and class discussion by showing a short video ("How Does Evolu on Really Work") available at www.pbs.org/wgbh/ evolu on/educators/teachstuds/svideos.html. Ac vity: Where did the horse come from? Divide the class into four groups, and provide each group with one of the four horse ancestor clue cards. (Alterna vely, for larger classes you may want to divide the class into groups of four and provide one clue card to each group member; however, this op on will require mul ple melines be provided as one is needed for each group. Only one meline is provided in the teaching kit.) Instruct students to examine their clue cards and the Horse Evolu on Timeline poster. Explain that students should match traits of each horse ancestor with the environmental condi ons which likely caused the development of those traits. Students should also communicate with their classmates to recognize trends in evolu onary development and order their clue cards based on these trends. One student representa ve from the group should tape their group's clue card to the appropriate area on the meline poster and write in a descrip on of why they placed that animal at that spot on the meline. (Because the poster is laminated, students may write with either dry erase or permanent markers. Permanent marker can be removed with rubbing alcohol or nail polish remover.) Have each group explain their placement and share their wri en response. Use their responses as the basis of discussion to elaborate on earlier class discussion about how evolu on works. Be sure to address the major evolu onary trends the horse experienced over
30 minutes Explain to the class that domes cated animals face different selec on pressures than animals that live in the wild. Wild animals adapt based on their environments. Since people control the breeding of domes c animals, they change over me due to selec ons made by people. Over me, domes c horses changed in appearance to suit the needs of the people who were breeding them. Ac vity: Horses and Their Uses Direc ons: Steps to follow: 1. Divide the class into groups of 4 or 5. 2. Have students brainstorm different ways horses are used by people today (i.e. racehorse, jumping horse, horse used for pulling buggy, rodeo or cow horse). 3. Ask students whether horses that perform each of these jobs would look the same. Why or why not? How would they be similar? How different? Assign one use to each group. Instruct students to build a model of the horse their group was assigned using Legos (provided in the teaching kit). You may provide students with some ideas by distribu ng the LEGO Horse Examples worksheet. Once each group has built their model, have groups share their models and explain why they built them as they did. 10 minutes Use the following ques ons to lead a class discussion reviewing and summarizing what students learned in the lesson. What are the differences between natural and ar ficial selec on? Do you know of any other domes c animal species that are grouped into different categories by their uses or traits? You may use this opportunity to discuss the development of breeds. Extension Ac vity 1: Horse Breeds Have students complete the short word find ac vity including names of different horse breeds. (15 minutes) Extension Ac vity 2: How many hands tall are you? Have students complete the How Many Hands Tall Are You? worksheet. Instruc ons for the ac vity are included on the worksheet. (25 minutes) Extension Ac vity 3: Maryland Horse Industry Sta s cs Have students research sta s cs on the Maryland Horse Industry and present their findings to the class. You may choose to have the students create posters or presenta ons to the class. Reliable sta s cal informa on is available from the Maryland Equine Census. <h p://www.mda.state.md.us/horseboard/census.html>
There are a variety of careers that involve horses and the equine industry. A good resource with many careers paths listed is The American Horse Council and the American Youth Horse Council. Remember that not all horse jobs revolve around direct contact with horses, so you can be crea ve in how you can apply your horse interests to other job fields. Direct Contact with Horses Veterinarian Veterinary technician Equine den st Therapist Riding instructor Auc oneer Rodeo professional Stallion manager Horse show manager Jockey Trainer Mounted police Farrier Indirect Contact with Horses University employee Extension educator Farm insurance agent Researcher Farm accountant Tack store owner Barn architect Writer Photographer Editor of equine publica ons Ac vity: Career Match A pre/post test should be completed with the lesson plan. Student understanding of concepts can also be evaluated through class discussion as well as through evalua on of completed ac vity data sheets. Analysis/ conclusion ques ons that are answered incorrectly by a large number of students should be addressed in a follow up discussion. American Horse Council and the American Youth Horse Council. Careers in the Horse Industry: Choose your Path. <h p://www.ayhc.com/pdfs/careers.pdf> extension HorseQuest Horse Breeds Informa on Website <h p://www.extension.org/pages/10353/what is a horse breed> breed. (n.d.). Merriam Webster's Medical Dic onary. Retrieved July 10, 2011, from Dic onary.com website: <h p://dic onary.reference.com/browse/breed> domes cate. (n.d.). Dic onary.com. Retrieved July 11, 2011, from Dic onary.com website <h p://dic onary.reference.com/browse/domes cate> Maryland Department of Agriculture. Equine Census. 2010 Oklahoma State University Breeds of Livestock Project: <h p://www.ansi.okstate.edu/breeds/horses/> Griffiths, J. 2088. Equine Science: Basic Knowledge for Horse People of All Ages. Gaithersburg, MD: Equine Network.
Eohippus Dawn Horse Mesohippus Middle Horse Pliohippus More Horse Equus First Horse Height 12 14 inches Approx. 24 inches Approx. 50 inches Over 53 inches Conforma on padded feet Four toes on each front foot and three toes on each back foot short face and neck arched back Diet Berries, fruit, herbs, other plants legs increasing in length three toes on each foot longer neck fla er back one single hoof beginning of the frog two other toes have receded to make splint bones long, muscular neck longer face strong, compact body one toe for the hoof long slender neck powerful limbs Foliage Grazed on the plains Grains, grasses and other forages Teeth Uneven, bumpy molars with shallow roots Fewer premolars than eohippus, roots are deeper Similar to that of the modern horse Similar to that of the modern horse Date of Origina on 50 55 million years ago (Eocene epoch) 40 to 20 million years ago (Oligocene epoch) 5 to 11 million years ago (Miocene epoch) Approximately 1 million years ago (Pliocene epoch) Environmental Condi ons Very hot Earth covered in forests Cooler temperatures Grasses developing Grasslands spreading Cooler Drier Seasonal climate
Where Did the Horse Come From? Clue Cards EOHIPPUS HEIGHT: 12 14 inches DIET: Berries, fruits, herbs CONFORMATION: Padded foot with toes (four on front and three behind); short neck and arched back MESOHIPPUS HEIGHT: about 24 inches DIET: foliage CONFORMATION: three toes on each foot; long legs and rela vely flat back
Where Did the Horse Come From? Clue Cards PLIOHIPPUS HEIGHT: about 50 inches DIET: grazed on grasses CONFORMATION: one dominant toe with two side toes receding; long neck and long face EQUUS HEIGHT: taller than 53 inches DIET: Grains, grasses, and other forages CONFORMATION: one toe (the hoof); Long neck and long face
LEGO Horse Examples
Name: Date: Period: Horses and ponies are measured in a unit called a hand with 1 hand = 4 inches. So a horse that is 60 inches tall is equal to 15.0 hands. Remember that to be considered a pony, the animal must not be taller than 14.2 hands, or 58 inches. Horses are taller than 14.2 hands. Let s see where you measure up! Have one of your group members stand up nice and tall and then using the hand given to you, measure your group member from foot (hoof) to the top of their shoulder (withers). Since from palm to finger p is longer than 4 inches, we use the hand sideways (finger ps poin ng to the side) to get an accurate measurement. Keep track of the number of hands and be sure to measure correctly. Make sure you write down the height you just measured and write down whether they would be considered to be a horse or a pony. Example: Bobby is 15.1 hands tall. He is a horse. is. He/she is a is. He/she is a is. He/she is a is. He/she is a is. He/she is a is. He/she is a......
Name: Date: Period: 0 4 1 2 3
Name: Date: Period: Horse Breeds Word Find N Q U A R T E R H O R S E Y R K Q Y I V S S P A C L N P E H J K A R N S X Y A O A R A B I A N O N O G D P I X V T U S O A Z D A S H N O L W Y L G V I O S E S T A N D A R D B R E D D L U H T P O M R D E I N Y E D J P M U S T A N G F L W T A O P D K X R I N Y C D E R B H G U O R O H T I Direc ons: Find each horse breed in the puzzle above. Then use the internet or other references to write a descrip on of each horse breed. APPALOOSA: QUARTER HORSE: ARABIAN: CLYDESDALE : THOROUGHBRED: WELSH PONY: MORGAN: PAINT: STANDARDBRED: MUSTANG:
PRE Evalua on: Horses and Evolu on 1. How old are you? 3. Are you.(select ALL that apply.) African American/Black 2. Are you.(select one.) A Boy Asian A Girl Hispanic/La no Na ve American/Alaskan Na ve Na ve Hawaiian/Other Pacific Islander White Other 4. What type of school do you go to? (Select one.) Public school Private school Religious school (Catholic, etc.) Home school Your Science and Agriculture Opinions and Knowledge 5. BEFORE going through the AGsplora on Program, please circle the degree to which you agree or disagree with the following statements. Strongly Disagree Disagree Agree I like science. 1 2 3 4 I feel that Maryland Agriculture is a part of science. 1 2 3 4 Science is useful for solving everyday problems. 1 2 3 4 Strongly Agree Maryland Agriculture is beneficial to me, my family, and my community. When I graduate from high school, I would like to have a job in agricultural science. 1 2 3 4 1 2 3 4 I can name three jobs in the agriculture industry. 1 2 3 4 6. BEFORE going through the AGsplora on Program, please circle your knowledge level about the topics listed below. None Low Medium High Maryland Agriculture 1 2 3 4 5 Types of horse breeds 1 2 3 4 5 Horse vocabulary 1 2 3 4 5 Uses of horses over me 1 2 3 4 5 Evolu on of the horse 1 2 3 4 5 Very High
POST Evalua on: Horses and Evolu on Your Science and Agriculture Opinions and Knowledge 5. AFTER going through the AGsplora on Program, please circle the degree to which you agree or disagree with the following statements. Strongly Disagree Disagree Agree I like science. 1 2 3 4 I feel that Maryland Agriculture is a part of science. 1 2 3 4 Strongly Agree Science is useful for solving everyday problems. 1 2 3 4 Maryland Agriculture is beneficial to me, my family, and my community. When I graduate from high school, I would like to have a job in agricultural science. 1 2 3 4 1 2 3 4 I can name three jobs in the agriculture industry. 1 2 3 4 6. AFTER going through the AGsplora on Program, please circle your knowledge level about the topics listed below. None Low Medium High Maryland Agriculture 1 2 3 4 5 Types of horse breeds 1 2 3 4 5 Horse vocabulary 1 2 3 4 5 Uses of horses over me 1 2 3 4 5 Evolu on of the horse 1 2 3 4 5 7. As a result of par cipa ng in this ac vity, tell one new thing you will try or one thing you will find informa on about. Very High
SUPPLEMENTAL Evalua on: Horses and Evolu on Direc ons: If you are teaching more than one lesson plan in one day, you may a ach this to the pre/post evalua on form for the other lesson you are teaching. Please have the student fill out these during the pre and post evalua on mes. In addi on, only have the student fill out the post evalua on ques ons Q5 Q7 at the comple on of all lessons. PRE Evalua on BEFORE going through the AGsplora on Program, please circle your knowledge level about the topics listed below. None Low Medium High Very High Maryland Agriculture 1 2 3 4 5 Types of horse breeds 1 2 3 4 5 Horse vocabulary 1 2 3 4 5 Uses of horses over me 1 2 3 4 5 Evolu on of the horse 1 2 3 4 5 POST Evalua on AFTER going through the AGsplora on Program, please circle your knowledge level about the topics listed below. None Low Medium High Very High Maryland Agriculture 1 2 3 4 5 Types of horse breeds 1 2 3 4 5 Horse vocabulary 1 2 3 4 5 Uses of horses over me 1 2 3 4 5 Evolu on of the horse 1 2 3 4 5