Name: _________________________________________________________________ Period: ________ Fossils, Natural Selection and Evolution
Packet - Regular
Components → 8.7.1 - 8.7.6
Agenda ● FOSSILS ● Do all organisms become fossils? → Page 2 ● Fossil Notes → Page 3 ● Sedimentary Rock Worksheet → Page 4 ● Relative vs Absolute Time → Page 5 ● Radioactive Half­Life Activity → Pages 6 ­ 7 ● Fossil Stations → Pages 8 ­ 10 ● Fossil Quiz → ▪
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Take the Fossil Quiz TOMORROW If you score less than a 70% ▪ Re­watch the notes video, study, retake the quiz TOMORROW ● EVOLUTION ● Evolution Notes → Page 11 ● Evolution Interactive → Pages 12 ­ 13 ● Evolution Stations → Pages 14 ­ 16 ● Evolution Quiz → ▪ Take the Evolution Quiz TOMORROW ▪ If you score less than a 70% ▪ Re­watch the notes video, study, retake the quiz TOMORROW ● NATURAL SELECTION ● Natural Selection Notes → Page 17 ● Natural Selection Computer Interactive → Page 18 ● Natural Selection Scenarios → Pages 19­20 ● Natural Selection Quiz → ▪ Take the Natural Selection Quiz TOMORROW ▪ If you score less than a 70% ▪ Re­watch the notes video, study, retake the quiz TOMORROW 1
AW 16 Name: _________________________________________________________________ Period: ________ Do All Organisms Become Fossils? Background: Fossils are made when a living thing dies and is buried by mud, silt, volcanic ash, or sand. Fossils could also be frozen in ice, mummified in hot or cold deserts, or preserved in tar. Usually, all of a living thing's soft parts decay, leaving only the hard parts to be buried, except when a living thing is frozen or mummified. The mud, silt, and sand are called sediments. The sediments have water with minerals in it. The minerals in the water soak into the hard parts, changing them into a rock like material and preserving the hard parts as fossils. Living things which die in or near oceans, lakes, or rivers have a better chance of fossilization than those which die on dry land, because they will be quickly buried. Over thousands and millions of years the sediments form heavy layers which slowly turn into sedimentary rock. Materials: ­ 3 Sugar cubes ­ 2 pieces of clay ­ 1 beaker ­ Spoon / Metal Scoop Procedure: 1. Sugar Cube 1 ● Take the larger piece of clay and wrap it tightly around the sugar cube so the entire cube is covered. Make sure there are no gaps 2. Sugar Cube 2 ● Take the smaller piece of clay and wrap it around the sugar cube so HALF the sugar cube is covered 3. Sugar Cube 3 ● Leave the third sugar cube alone. 4. Fill the beaker ¾ full of water 5. Place all 3 sugar cubes into the beaker of water 6. Gently stir the cubes in water for 45 seconds using the metal scoop 7. Remove the cubes from the water and examine the remains. 8. Observe what happens and answer the questions below. Analysis Questions: Describe what happened with each sugar cube #1 #2 #3 1. What needs to occur to an organism in order for it to become a fossil? 2. List 2 ways an organism can be preserved in nature. What in nature could replace the clay? ●
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3. What could happen to prevent an organism from becoming a fossil? 2
AW 16 Name: _________________________________________________________________ Period: ________ Fossil Notes What is a fossil? • Remains of once living animals or plants that represent ancestors of organisms living today Does every organism turn into a fossil? • No ‐ ___________________________________________________________ • They need perfect condi逐ons → ____________________________ / undisturbed How are fossils formed? 1. Animal dies and is buried by sediment 2. Extreme pressure turns sediment into sedimentary rock 3. Skeleton dissolves and leaves a hole/mold – Dissolved by groundwater 4. Minerals crystallize in hole and a cast is formed – Mineral rich water enters mold and leaves minerals 5. Millions of years later, the fossil is exposed on the Earths surface – Earthquakes, building, construc逐on, digging / drilling What do fossils tell us? • Which organisms were alive in the past • The diversity of the types of organisms that were present at any given 逐me. • Which organisms became ex逐nct when (and why) • How organisms have evolved over 逐me. • To see how organisms are related • To see how (individual vs group) and where organisms used to live. • To have a be␈er understanding of the world around us How do we get information about fossils? • Type of Fossil – ___________________ → Tell us what the animal / plant looks like • Ex: Petrified wood, frozen mammoths, amber – ___________________ → Tell us what the animal did • Ex. Footprints, trackways, Coprolites (poo) • Age of Fossil ●
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RELATIVE DATING Approximate 逐me scale ____________________________ Used when fossils / rock layers in layers too old for absolute da逐ng Informa逐on provided ○ Approximately when animals lived ○ Which animals lived in the same 逐me periods ○ What natural disasters happened (earthquakes, volcanoes, droughts) and when they occurred ○ Think: Grand Canyon! ABSOLUTE DATING ●
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Specific 逐me scale _________________________________ More accurate Informa逐on Provided ○ Specific age of the fossil ○ Can only be used up to 70,000 years (depending on the element used) How it Works: ○ Certain naturally occurring elements are radioac逐ve and they break down at predictable rates ○ Scien逐sts use these rates to measure the half‐life of elements ■ Half life = the 逐me it takes for HALF of the radioac逐ve element to break down ○ Scien逐sts compare the amount of an element to the ini逐al amount and the half‐life to determine age ■ If each half‐life is 5,730 years old and the sample is 2 half lives then it is 11,460 years old (2 X 5,730 = 11,460) 3
AW 16 Name: _________________________________________________________________ Period: ________ Sedimentary Rock Worksheet Sedimentary rocks are par逐cularly important in the understanding of the Earth’s history. These rocks are formed at the Earth’s surface as layers of sediment (small par逐cles broken down from other rocks) build up, and pressure compresses them into rock. Each layer of rock records the nature of the environment at the 逐me that it was laid down. The layers are the characteris逐c feature of sedimentary rocks, the oldest ones being located at the bo␈om of the sequence as they were deposited first. Fossils are probably the most important inclusions found in sedimentary rocks. Knowing something about these prehistoric life‐forms and the rock they are found in can help us to recreate environments and ecosystems from the past. Use the pictures on the right to answer the following questions. 1. Which shell is the oldest? 2. There are no shells in Layer 3, why might this be? 3. No dinosaur bone is found below Layer 2, this might mean: 4. If you also found a so袈袈 drink can in Layer 4, what could you say about Layers 4, & 5? Some逐mes rocks are reshaped as a result of movement. This can be seen when rock layers are not simple straight layers or no longer match up. Faul逐ng occurs when the rock layers move along a weak point or fault line. Fossils are some逐mes used to match layers that are no longer con逐guous. Some folded or faulted forma逐ons may then be eroded to a flat surface before more layers of sediment are deposited on the surface. This is called an unconformity 5. In diagram I, which layer is the same as Layer A? 6. In diagram II, which layers do you think were laid down in the Ocean? 7. Which were deposited on or near land? 8. How can you tell the condi逐ons of each layer (where they were deposited / laid down)? 9. What informa逐on can the layers tell you about the organisms found there? ● ●
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AW 16 Name: _________________________________________________________________ Period: ________ Relative vs. Absolute Time Background: By knowing the age of the rock that a fossil is found in, geologists can usually tell the age of the fossil. Some逐mes they cannot give it an exact date, but they know that it is older or younger than another fossil. Da逐ng a fossil by saying it is older or younger than another fossil is called rela逐ve da逐ng. If the geologists know the exact age of a fossil, they usually express its age in millions of years ago (mya) that it was formed. Scien逐sts use radioac逐ve half‐life data to determine a fossils age. Da逐ng a fossil by assigning it a specific age is called absolute da逐ng. Procedure: 1. Make a rela逐ve 逐me scale out of 7‐8 events that have occurred in your life. a. Ex. Include important events such as your birth, star逐ng kindergarten, or losing your first tooth. b. REMEMBER: These events only show chronological order, NOT exact dates 2. Using your rela逐ve scale, make an absolute 逐me scale by adding dates 3. Answer the analysis ques逐on below Example: Example Time Scale Relative Time Scale Absolute Time Scale I was born. I took my first steps. My li␈le sister was born First high school RBI Graduated high school Graduated college Got my first job Today I was born August 21, 1985 I took my first steps July 15, 1986 My li␈le sister was born May 30, 1988 First high school RBI March 21, 2001 Graduated high school May 28, 2004 Graduated college May 31, 2008 Got my first job August 26, 2009 Today November 30, 2013 Relative Time Scale Absolute Time Scale I was born. I was born. My Time Scale: Today Today Analysis Question: 1. Why are both relative time and absolute time to reconstruct past timescales? 5
AW 16 Name: _________________________________________________________________ Period: ________ Radioactive Half­Life Background: One characteris逐c of radioac逐ve material is that radioac逐ve isotopes spontaneously give off par逐cles. This process, called radioac逐ve decay, changes the nucleus of the material. The length of 逐me it takes for half of a sample of radioac逐ve material to decay is called the half‐life. Each radioac逐ve isotope has a characteris逐c half‐life, ranging from less than a second to millions of years. Carbon‐14 is a special unstable element used in the absolute da逐ng of material that was once alive, such as fossil bones. Every 5,730 years, half of the carbon‐14 in a fossil specimen decays or breaks down into a more stable element. In this ac逐vity, you will use pennies that can land “heads up” (nuclei that have undergone radioac逐ve decay) or “tails up” (nuclei that haven’t yet decayed) as a simplified model of half‐life. The pennies represent the radioac逐ve isotopes and each round represents the number of years it takes to decay by half (hence half‐life) Procedure: 1. There is a video explaining how to do this lab if any of the direc逐ons below are confusing 2. Trial 1 a. Count to make sure you have 100 pennies b. Shake the pennies up in the cup and roll them into the box lid c. Count how many pennies are heads up and record the data below d. Place the pennies that are heads up back in the cup e. Place the pennies that are tails up in the basket/tray f. Repeat steps b ‐ e five more 逐mes ● Make sure you are recording your data below ● Each round you should start will LESS pennies 3. Trial 2 and 3 a. Repeat each of the steps above 4. Average your data from the three trials a. To average, add all three numbers together for each round and divide it by 3 5. Type your averages in the class excel document → The excel document can be found in the 8th Grade S逐rred Science folder on the shared drive 6. Write the class data in the chart below (only if 5 groups have recorded their data ‐ you might have to wait) 7. Look at the graph created (Tab 2 ‐ At the bo␈om of the page) to answer the analysis ques逐ons a. Wait un逐l at least 5 groups have typed in their data Data: INDIVIDUAL DATA CLASS DATA # of Pennies at the beginning of each round Round Trail 1 Trail 2 Trial 3 Individual Average Round Class Average 0 100 100 100 100 0 100 1 2 3 4 5 6 6
1 2 3 4 5 6 AW 16 Name: _________________________________________________________________ Period: ________ Analysis Questions: 1. When do we use radioac逐ve half life? 2. Give a situa逐on where you cannot use radioac逐ve half‐life to determine the age of a fossil. 3. What did the pennies represent? 4. What did each trial represent? 5. Compare your graph with the “Half‐life of Carbon‐14” graph on the right. What similari逐es do you see? 6. Why is radioactive decay more helpful for determining the age of fossils than absolute dating? 7. Is radioac逐ve decay always the best for determining the age of a fossil? Why or why not. 8. If a “sample” of pennies contained 75 heads and 25 tails, how many half‐lives would have passed since the “sample” formed. Explain your answer. 9. If each half‐life was 2000, years how many years old would the above sample be? 10. If a “sample” of pennies contained 25 heads and 75 tails, how many half‐lives would have passed since the “sample” formed. Explain your answer. 11. If each half‐life was 2000, years how many years old would the above sample be? 7
AW 16 Name: _________________________________________________________________ Period: ________ Fossil Station Activity Station 1 1. What can a complete fossil record tell us? ● ● ● ● ● Station 2 2. Diagram 1: Identify the layers from OLDEST to YOUNGEST Oldest _____, _____, _____, _____, _____ Youngest 3. Diagram 2: Identify the layers from OLDEST to YOUNGEST Oldest _____, _____, _____, _____, _____, _____ Youngest 4. Diagram 3: ADVANCED: Identify the layers from OLDEST to YOUNGEST Oldest ____, ____, _____, _____, _____, _____, _____, _____ Youngest Station 3 5. Which two layers are the youngest? 6. Which layer at Site 1 happened at the same time as letter Y. 7. Put the layers at Site 2 in order from oldest to youngest. 8. Which organisms are now extinct? 9. Besides extinction why could fossils not be found in a certain layer? ●
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AW 16 Name: _________________________________________________________________ Period: ________ Station 4 10. Complete the following chart Grams of C­14 Number of half lifes Amount of time that has passed (years) 24 0 0 11. How many half lives is the wood? 12. How many years old is the wood? Station 5 13. The following fossil was located 200 miles above sea level on a mountain. Compare its original environment to its current one and explain how it got here. ● Original environment: ● Current environment: ● How did it get here? Station 6 ­ https://www.youtube.com/watch?v=3rkGu0BItKM Watch the Fossil YouTube video and answer the following questions 9. What are two examples of situations where an entire organism might be preserved as a fossil instead of just their bones? ● ●
10. What is a natural mold? 11. If a fossil from millions of years ago is dug up, does it contain bone? Explain why or why not. 12. What are four examples of how fossils become found / exposed to the surface? ●
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AW 16 Name: _________________________________________________________________ Period: ________ Station 7 ­ http://www.amnh.org/ology/features/layersoftime/game.php Procedure ● Go to the Rock Layers game ● Go through the intro ● Select Level 1 ● Once you think you are done, check your work and continue working until you get it correct. ● COMPLETE ALL 3 LEVELS 13. What did you learn from the game? Station 8 14. How does the number of marine families change from 600 to 1 million years ago? (Provide specific numbers) 15. What is the line not straight? Why doesn’t it go on a perfect diagonal? 16. Why are jawless fishes (in the devonian era) no longer found today? 17. How many marine families to do we have today? Station 9 18. How does the Compsognathus compare to the Gallus Compsognathus Gallus 10
AW 16 Name: _________________________________________________________________ Period: ________ Evidence of Evolu逐on Evolu逐on • Defini逐on: – ________________________________________________________ • Takes a Looooong 逐me Results from a change in the ______________ material of an organism – Not acted on at the individual level – Passed on from one genera逐on to the next Evidence for Evolu逐on • Similari逐es of structures in living things – Analogous Structures • ______________ func逐on • Ex. Used to fly • ______________ structure • Ex. Different arrangement of bones • ______________ origins • Do not have a common ancestor – Homologous Structures • ______________ structure • Same basic arrangement of bones • ______________ func逐on • Adapted to different purposes • Humans arm is used differently than a whales fin • ______________ origin • Common ancestor – Embryo development (early stages) • Embryos develop similarly in many vertebrates – Ves逐gial Organs • Inherited structures that no longer serve a func逐on for the organism • Examples • Hipbone in dolphin/whale • Our appendix • Our wisdom teeth • Shared Ancestry – The fossil record • Found fossils that show slow progression of change – Biogeography • Found animals in isolated islands or environments that ended up being perfect for that area a袈袈er genera逐ons • Where they are now compared to then • Pa␈erns in different places tell how organisms evolved • Popula逐ons on different islands all look different… • Originate from a mainland • Ex: Galapagos Islands • Change over 逐me… • Depending on the food source and environment, different birds survived and changed to best fit each island 11
AW 16 Name: _________________________________________________________________ Period: ________ Evolu逐on Interac逐ve Go to the following link and follow the instruc逐ons below. h␈p://evolu逐on.berkeley.edu/evolibrary/ar逐cle/similarity_ms_01 Similarities and Differences 1. Define homology 2. Click on “common ancestor” and write down the defini逐on 3. Define analogy 4. Click on “convergent evolu逐on” and write down the defini逐on 5. PRESS NEXT (Bo␈om Right) The Tale of the Limb 6. Read the direc逐ons 7. Play the game (un逐l you have all 4 limbs on the screen. “It will say play again when you are finished”) 8. PRESS NEXT (Bo␈om Right) The Tetrapod Limb 9. A tetrapod is an organism that contains vertebrates with sturdy limbs (and not fins), how are all of the tetrapod limbs similar? 10. Scroll down to the bo␈om 11. Click on each limb to match its owner (write down the correct answers) 12. PRESS NEXT (Bo␈om Right) Inheriting Homologies 13. Read the page carefully 14. In a family tree, ______________________________________________________________________ 15. In an evolu逐onary tree, _______________________________________________________________ 16. Define homologous structures 17. PRESS NEXT (Bo␈om Right) 12
AW 16 Name: _________________________________________________________________ Period: ________ Homologies are Everywhere 18. Give examples of organisms that are obvious homologies ● ●
19. Give examples of organisms that it is not obvious they are homologies 20. PRESS NEXT (Bo␈om Right) Not all similarity is homologous 21. Scroll down the page and read carefully 22. Homologies are inherited from ____________________________ 23. Define analogous structures 24. PRESS NEXT (Bo␈om Right) Analogies 25. Scroll down the page and read carefully 26. Are the Sabertooth sculls on the page analogous or homologous? 27. PRESS NEXT (Bo␈om Right) How do analogies evolve? 28. Scroll down and read 29. What is the advantage of having a streamlined body shape? 30. Are dolphins and sharks from the lineage/ ancestor? 31. Are dolphins and sharks streamlined bodies and flippers analogous or homologous? 32. PRESS NEXT (Bo␈om Right) Test your understanding 33. Scroll down the page and read carefully 34. Are the “wings” of the sugar gliders and flying squirrels homologous or analogous structures? More Details 35. If you want to see addi逐onal examples of homology and analogy click the links in the top right corner of your page! 13
AW 16 Name: _________________________________________________________________ Period: ________ Evolu逐on Sta逐ons Station 1: 1. What func逐on do each of the structures in image A and B perform? 2. Complete the chart below Set A Set B Similarities Differences Evidence for Evolution (Analogous or homologous) 3. Which set of wings in more similar? 4. Why? Station 2 5. What func逐on do each of the structures perform? 6. What similari逐es do you observe? 7. What differences do you observe? 8. The organism in the picture are ______________ (analogous, homologous) and all have a ______________ (common, different) ancestor. 14
AW 16 Name: _________________________________________________________________ Period: ________ Station 3 9. Describe each organism from the image in the chart below 1st Image Fish ‐
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Very li␈le detail Curved body Small gill slits near head Longer tail 2nd Image ‐
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Body straightens out Fins and gills start developing Tail elongates 3rd Image ‐
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Head and face develop Fins on back develop Body becomes wider Tail becomes stronger Turtle Salamander Human 10. Why is it important to study the development of an organism star逐ng from the embryo stage? Station 4 11. Why might a whale have a hipbone if it doesn’t walk or use it for any purpose? 12. A friend or family member goes into surgery and has their appendix removed. Why are they able to live a long healthy life? 13. Why do you think we have wisdom teeth if we don’t need them? 14. Provide one more example of a ves逐gal structure within humans. 15
AW 16 Name: _________________________________________________________________ Period: ________ Station 5 15. If you just had the fossils from Echippus and Equus would you say they had a common ancestor? 16. Why is it so important to find fossils? 17. How have horses changed over the years? 18. What could have caused the horses to change? Station 6: Biogeography 19. How can being located in a different area change a species? 20. How might a species change over 逐me if it moves to a colder climate? 21. How might a species change over 逐me if it moves to a habitat that is a different color? 22. How might a species change over 逐me if a new predator moves into the area? Station 7: Vestigal Structures → h␈ps://www.youtube.com/watch?v=rFxu7NEoKC8 1. Do you have the ves逐gal tendon in your wrist? 2. What animal has the longest palmaris longus muscle? 3. Can you wiggle your ears? 4. Are goosebumps necessary for humans? 16
AW 16 Name: _________________________________________________________________ Period: ________ Natural Selec逐on Notes What is evolution? • Defini逐on: • ________________________________________________________ • Takes a Looooong 逐me • Results from a change in the ______________ material of an organism • Not acted on at the individual level • Passed on from one genera逐on to the next Darwin vs. Lamarck Lamarck Darwin Developed 1st idea about how organisms get their traits Developed current idea about how organisms get their traits When an individual organism acquires a new trait __________________________________________ it passes that trait to its offspring All organisms are _______________________________________ and when that organism reproduces the traits get passed on to its offspring Ex. A giraffe wanted to reach a higher tree so it stretched Ex. Giraffes were all born with different heights. The ones with its neck. This longer neck was passed onto the next longer necks were more “fit” and they were able to get addi逐onal genera逐on food, survive, and pass on those traits. NO EVIDENCE!!!!!!! Years of evidence! What is natural selection? • Darwins idea! • The process through which members of a species are best suited to their environment survive and reproduce at a higher rate than other less suited members of the species • __________________________________________ • The most “fit” animals will be selected for and will survive. • Species adapt to their environment • Adapta逐on: A characteris逐c, a behavior, or an inherited trait • Fitness: How well you are equipped to survive the environment you live in Natural Selection Overproduction When a plant or an animal reproduces it usually creates ______________ offspring than the environment can support Ex. Salmon lay 100’s of eggs but only a few will survive Variation Adaptation Selection Within a species there are Muta逐on that makes an _________________________ individual be␈er able to due to muta逐ons (change in DNA) survive Gives organism an Gene逐c varia逐ons are passed from one genera逐on to the next ______________ Individual organisms with a par逐cular adapta逐on will survive long enough to reproduce Adapta逐on becomes ________________________ in next genera逐on New Species Evolve from Earlier Species • Specia逐on: ______________________________________________________________________ • May occur when the environment changes drama逐cally or gradually • Species can also be isolated if they feed on different things or reproduce at different 逐mes of year 17
AW 16 Name: _________________________________________________________________ Period: ________ Natural Selec逐on Computer Interac逐ve h␈ps://askabiologist.asu.edu/sites/default/files/PepperMoth/pepper‐moths.swf Read the background informa逐on and answer the ques逐ons as you go. Life Cycle of the Peppered Moth 1. Why are these moths called "peppered moths?" 2. What animals eat the peppered moth? Impact of Pollution 3. What caused the Industrial Revolu逐on? 4. What was the Industrial Revolu逐on's impact on the trees? Why did it impact the trees? ● ● 5. What was causing the different colors in the moths? 6. What is natural selec逐on? Birdseye View 7. Open the simula逐on and play the role of the bird in both the dark and the light forest. Try to behave as a bird would behave, choosing the moths that are the most obvious. At the end of each simula逐on, record the percent of moths captured in the table. Percent Dark Moths Percent Light Moths Light Forest Dark Forest Final Analysis 8. Explain how the color of the moths increases or decreases their chances of survival. ● 9. What would happen if there were no predators in the forest? Would the colors of the moths change over 逐me? Defend your answer? ● ● ● 18
AW 16 Name: _________________________________________________________________ Period: ________ Natural Selection Application Questions 1. A lot of research has gone into the idea that birds are descendants of dinosaurs. At some point, a muta逐on occurred that made feathers pop up. Why do you think feathers stayed around and wasn’t one of the muta逐ons that just disappeared a袈袈er a genera逐on or two? 2. If you get a flu shot one year why would you need to get it the next year? Why you aren’t s逐ll protected from the flu? 3. What happens to animals that cannot compete as well with other animals in the wild? ●
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4. Some逐mes animals that are introduced into an area that they never lived in before, outcompete and endanger resident species, why do you think this happens? 5. If only one species is considered the "fi␈est", why do we s逐ll have so many varia逐ons among species. Why do some birds have very long pointy beaks, while other birds have short flat beaks? 6. How do you think diseases can affect natural selec逐on? 7. There are two types of rabbits: those that strictly eat grass and those that strictly eat berries and flowers. A drought occurs one year, and the plants have difficulty producing any extras (flowers, berries, etc.). What does the rabbit popula逐on look like in 10 years? Why? 8. Bob believes that giraffes have long necks because they have stretched their necks to try and reach food that is high in trees. Since the parent had stretched its neck, it passed the long neck onto its offspring. Ryan believes that giraffes have long necks because the ones with long necks were able to reach the food, and those with short necks could not and died. The long necked giraffes reproduced, and soon all of the giraffes had long necks. ● ● 19
AW 16 Name: _________________________________________________________________ Period: ________ Use the image below to answer the following ques逐ons 9. Why is the popula逐on of mice different in figure 3 than in figure 1? 10. Living things that are well adapted to their environment survive and reproduce. Those that are not well adapted don’t survive and reproduce. An adapta逐on is any characteris逐c that increases fitness, which is defined as the ability to survive and reproduce. What characteris逐c of the mice is an adapta逐on that increased their fitness? 11. The table below gives descrip逐ons of four female mice that live in a beach area which is mostly tan sand with sca␈ered plants. According to the defini逐on given for fitness, which mouse would biologists consider the fi␈est? Explain why this mouse would be the fi␈est. 12. If a mouse's fur color is generally similar to its mother’s color, what color fur would be most common among the pups? 20
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