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Ch. 32 - Deuterostome Animals
All textbooksFreeman 8th EditionCh. 32 - Deuterostome AnimalsProblem 11
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Chapter 31, Problem 11

The size and shape of the vertebrate skull can reveal a great deal about an animal's lifestyle and evolutionary relationships. Consider your own skull. If you put your finger in your ear and move your jaw up and down, you can feel the space near the hinge of your jaw. Nestled in this space are the tiny bones that make your hearing possible: the malleus, incus, and stapes. All mammals have these three ear bones, but reptiles such as this T. rex don't. Where did ear bones come from? Analyze the morphological data shown here and write a hypothesis to explain the origin of mammalian ear bones. (The cynodont shown is one of many extinct synapsid amniotes that lived early in the lineage that gave rise to mammals.)

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Hello everyone and welcome to today's video. So today we need to identify the statement about mammals that is not true. Remember that. We're looking for the incorrect statement and modern answer choices. So here we're given three statements from where we need to select the incorrect one. Let's begin by statement. All mammals have a school. I want you to touch the top of your head and you're going to realize that you in fact have a school and this is because most mammals share this career. This is a correct statement. So we're going to cancel it out because we're looking for the incorrect one. Then we have all mammals have three ear bones, the Incas the mallows and disables. That is actually a correct statement. And in fact the popular names for these bones or the hammer, the anvil and the syrup. So this is what they are popularly called. This is like I said a correct statement. So we're going to cancel it because we're looking for the incorrect one. Then we have statements are mammals all are jealous. They do not have a job. Well humans in fact I have a job. So this statement cannot be correct because it does not apply to humans which are mammals because of this. This is going to be the only incorrect statement and modern answer choices which is going to be reflected by answer choice. C That is the end of the video and I really hope this helped you
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Textbook Question

Consider the evolution of protostomes and deuterostomes (this chapter): (1) Compare adaptations in protostomes and deuterostomes for living on land. (2) Recall that changes in the expression patterns of tool-kit genes in arthropods such as insects enabled a dramatic diversification of their segmented appendages and bodies. Design an experiment to test whether this concept applies to vertebrates.

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Genetic diversity in living human populations is highest in Africa and decreases as a function of distance traveled by the human migration that left Africa many millennia ago. Draw a graph to show this trend. (Hint: What is the independent variable? What is the dependent variable? What kind of graph is appropriate for this kind of data? Add a label where you would expect to find a data point for the Yanomamö tribe of the Amazon rain forest in South America. Why is it important to use indigenous people for this study?

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Textbook Question

Humans possess which of the following traits? Select True or False for each trait. T/F triploblasty T/F parthenogenesis T/F viviparity T/F metamorphosis

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Textbook Question

The size and shape of the vertebrate skull can reveal a great deal about an animal's lifestyle and evolutionary relationships. Consider your own skull. If you put your finger in your ear and move your jaw up and down, you can feel the space near the hinge of your jaw. Nestled in this space are the tiny bones that make your hearing possible: the malleus, incus, and stapes. All mammals have these three ear bones, but reptiles such as this T. rex don't. Where did ear bones come from? How is the opossum related to you? Select True or False for each statement. T/F An opossum is an animal, but I am a human. T/F An opossum is a mammal, but I am a human. T/F An opossum is a marsupial, but I am a placental mammal. T/F The opossum and I are both tetrapods.

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Textbook Question

The size and shape of the vertebrate skull can reveal a great deal about an animal's lifestyle and evolutionary relationships. Consider your own skull. If you put your finger in your ear and move your jaw up and down, you can feel the space near the hinge of your jaw. Nestled in this space are the tiny bones that make your hearing possible: the malleus, incus, and stapes. All mammals have these three ear bones, but reptiles such as this T. rex don't. Where did ear bones come from? The illustration of the opossum skull shows that the ear bones are completely separated from the jawbone (as they are in all mammals). Pose a hypothesis to explain why this separation could be an adaptation that contributed to the radiation of mammals into diverse niches, including a nocturnal lifestyle.

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Textbook Question

The size and shape of the vertebrate skull can reveal a great deal about an animal's lifestyle and evolutionary relationships. Consider your own skull. If you put your finger in your ear and move your jaw up and down, you can feel the space near the hinge of your jaw. Nestled in this space are the tiny bones that make your hearing possible: the malleus, incus, and stapes. All mammals have these three ear bones, but reptiles such as this T. rex don't. Where did ear bones come from? Gene expression patterns can be used to test hypotheses based on morphology. For example, the regulatory gene Bapx1 is expressed in the hinge of the developing lower jaw in fishes and reptiles. Where would you predict Bapx1 expression to occur in mammals?

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