Animation Description
The animation that accompanies this multiple choice question shows images of seven animals, shark, tuna, frog, human, hare, caiman, and parrot, connected by a branching evolutionary tree beneath them. An arrow shows that time progresses in the upwards direction on the tree. On the tree proceeding upwards, a horizontal line on the root marked "vertebrae" indicates that vertebrae evolved in the common ancestor of all the animals on the tree. Then the branch leading to the shark splits off to the left. On the other branch (which leads to the remaining animals), "bony skeleton" evolved. Then the branch leading to the tuna splits off to the left. On the other branch (which leads to the remaining animals), "four limbs" evolved. Then the branch leading to the frog splits off to the left. On the other branch (which leads to the remaining animals), "amniotic egg" evolved. Then a branch splits off to the left that itself splits into two, leading to the human and hare. At the base of this branch, "hair" evolved. The last branch, which extends up and to the right splits into the caiman and parrot branches. At the base of this branch, "opening in front of eye" evolved. To the right of the seven animals, T. rex appears but is not connected to the evolutionary tree. The trait "vertebrae" is highlighted, and all seven animals on the tree have + signs underneath them, indicating that they have inherited vertebrae. There is a blank space under T. rex. The panel with the multiple choice question shows a photo of T. rex skeleton with a backbone. When the first option (+ T. rex has vertebrae) is clicked, a + appears underneath T. rex and a red line appears connecting the lineages leading to all seven taxa and underneath T. rex, indicating that they all have vertebrae. When any other option is clicked, the user is instructed to "Try again." After selecting the correct answer, the reader is presented with another multiple choice question asking about a bony skeleton. The trait "bony skeleton" is highlighted, and all the animals on the tree except the shark have + signs underneath them, indicating that they have inherited a bony skeleton. The shark has a zero underneath it. There is a blank space under T. rex. The panel with the multiple choice question shows a photo of T. rex skeleton with a backbone. When the first option (+ T. rex has a bony skeleton) is clicked, a + appears underneath T. rex and a red line appears connecting the lineages leading to the six taxa with a + sign and underneath T. rex, indicating that they all have a bony skeleton. When any other option is clicked, the user is instructed to "Try again." After selecting the correct answer, the reader is presented with another multiple choice question asking about four limbs. The trait "four limbs" is highlighted, and all the animals on the tree except the shark and tuna have + signs underneath them, indicating that they have inherited four limbs. The shark and tuna have zeros underneath them. There is a blank space under T. rex. The panel with the multiple choice question shows a photo of T. rex skeleton with two arms and two legs. When the first option (+ T. rex has four limbs) is clicked, a + appears underneath T. rex and a red line appears connecting the lineages leading to the five taxa with a + sign and underneath T. rex, indicating that they all have four limbs. When any other option is clicked, the user is instructed to "Try again." After selecting the correct answer, the reader is presented with another multiple choice question asking about the amniotic egg. The trait "amniotic egg" is highlighted, and human, hare, caiman, and parrot have + signs underneath them, indicating that they have inherited an amniotic egg. The shark, tuna, and frog have zeros underneath them. There is a blank space under T. rex. The panel with the multiple choice question shows a diagram of an egg in an embryo being nourished via organs within the egg. When the third option (? we don't know) is clicked, a ? appears underneath T. rex and a red line appears connecting the lineages leading to the four taxa with a + sign, indicating that they all have amniotic eggs but we don't know if T. rex did. When any other option is clicked, the user is instructed to "Try again." After selecting the correct answer, the reader is presented with another multiple choice question asking about hair. The trait "hair" is highlighted, and the human and hair have + signs underneath them, indicating that they have inherited hair. The other five animals on the tree have zeros underneath them. There is a blank space under T. rex. The panel with the multiple choice question shows a photo of T. rex skeleton. When the last option (? we don't know) is clicked, a ? appears underneath T. rex and a red line appears connecting the human and hare lineages, indicating that they have hair. In the panel at right, a playful reconstuction of an angry T. rex with hair is shown. When any other option is clicked, the user is instructed to "Try again." After selecting the correct answer, the reader is presented with another multiple choice question asking about an opening in front of the eye. The trait "opening in front of eye" is highlighted, and the caiman and parrot have + signs underneath them, indicating that they have inherited an opening in front of the eye. The other five animals on the tree have zeros underneath them. There is a blank space under T. rex. The panel with the multiple choice question shows a photo of T. rex skull with a green highlighted opening between the eye socket and the nostril. When the first option (+ T. rex has an opening in front of the eye) is clicked, a + appears underneath T. rex and a red line appears connecting the parrot and caiman, and underneath T. rex, indicating that they all have an opening in front of the eye. When any other option is clicked, the user is instructed to "Try again."
Animation Text
Vertebrae
Let's start with vertebrae.
Look at the T. rex skeleton below. What would you write in the table for T. rex?
+ T. rex has vertebrae
- T. rex lacks vertebrae
? we don't know
Responses
- T. rex has vertebrae; Correct answer text: Correct!
- T. rex lacks vertebrae; Incorrect answer text: Oops. Look more closely at the picture of T. rex to see if it has a backbone or not. Try again.
? we don't know; Incorrect answer text: Oops. Does T. rex have a backbone or not? Try again.
Bony skeleton
But did T. rex have a bony skeleton? What would you write in the table?
+ T. rex has a bony skeleton
- T. rex lacks a bony skeleton
? we don't know
Responses
- T. rex has a bony skeleton; Correct answer text: Correct!
- T. rex lacks a bony skeleton; Incorrect answer text: Oops. Look more closely at the picture to see if T. rex has a skeleton made of bone.
? we don't know; Incorrect answer text: Oops. Look more closely at the picture to see if T. rex has a skeleton made of bone.
Four limbs
Does T. rex have four limbs? How would you mark the table?
+ T. rex has four limbs
- T. rex lacks four limbs
? we don't know
Responses
- T. rex has four limbs; Correct answer text: Great! T. rex was a tetrapod.
- T. rex lacks four limbs; Incorrect answer text: Oops. Remember that tetrapods are animals that inherited four bony limbs. Look for the two small arms and the two legs.
? we don't know; Incorrect answer text: Oops. Remember that tetrapods are animals that inherited four bony limbs. Look for the two small arms and the two legs.
Amniotic egg
But did T. rex inherit an amniotic egg? Focus just on what we might be able to figure out from fossils. What would you write in the table?
+ T. rex has an amniotic egg
- T. rex lacks an amniotic egg
? we don't know
Responses
- T. rex has an amniotic egg; Incorrect answer text: Oops. Can we really tell if T. rex was an amniote or not?
- T. rex lacks an amniotic egg; Incorrect answer text: Oops. Can we really tell if T. rex was an amniote or not?
? we don't know; Correct answer text: Correct! The fossil record for T. rex does not indicate the presence or absence of such a feature, so we can't be sure.
Hair
Did T. rex have hair like humans and hares? Focus just on what we might be able to figure out from fossils.
+ T. rex has hair
- T. rex lacks hair
? we don't know
- T. rex has hair; Incorrect answer text: Oops. Can we really tell if T. rex had hair or not?
- T. rex lacks hair; Incorrect answer text: Oops. Can we really tell if T. rex had hair or not?
? we don't know; Correct answer text: That's right! There's no fossil evidence to indicate that T. rex had or did not have hair.
Opening in front of eye
Look closely at the T. rex skull. Mark in your table whether T. rex has a skull opening in front of the eye or not?
+ T. rex has an opening in front of the eye
- T. rex lacks an opening in front of the eye
? we don't know
- T. rex has an opening in front of the eye; Correct answer text: Correct! T. rex inherited a skull opening in front of the eye.
- T. rex lacks an opening in front of the eye; Incorrect answer text: Oops. Look closely at the skull and count the number of openings that you see.
? we don't know; Incorrect answer text: Oops. Look closely at the skull and count the number of openings that you see.
Before we move on, take some time to update your table. You can check your work here https://ucmp.berkeley.edu/trex-module/folder-4/folder-4n/.