Podcast
Questions and Answers
What is the significance of the ability to form mineralized tissues in the skin for all vertebrates?
What is the significance of the ability to form mineralized tissues in the skin for all vertebrates?
It is a feature of all vertebrates from ostracoderms onward.
How many times may the production of teeth or toothlike structures have evolved independently among vertebrates?
How many times may the production of teeth or toothlike structures have evolved independently among vertebrates?
Several different times.
What changed ideas about early vertebrate interrelationships according to the text?
What changed ideas about early vertebrate interrelationships according to the text?
Accepting conodonts as vertebrates.
What is the importance of mineralized tissues in the vertebrate phylogeny?
What is the importance of mineralized tissues in the vertebrate phylogeny?
Why are the toothlike structures of conodonts and the bony dermal skeletons of ostracoderms considered to make them more derived vertebrates?
Why are the toothlike structures of conodonts and the bony dermal skeletons of ostracoderms considered to make them more derived vertebrates?
What characterized the body fluids of early vertebrates and invertebrates in terms of osmolal concentration?
What characterized the body fluids of early vertebrates and invertebrates in terms of osmolal concentration?
What unique feature do hagfishes possess in terms of gland openings?
What unique feature do hagfishes possess in terms of gland openings?
What is the purpose of the slime produced by hagfishes?
What is the purpose of the slime produced by hagfishes?
How do hagfishes get rid of the mass of mucus after producing it?
How do hagfishes get rid of the mass of mucus after producing it?
What is the internal anatomy characteristic of hagfishes in terms of vertebrae?
What is the internal anatomy characteristic of hagfishes in terms of vertebrae?
Describe the eyes of hagfishes.
Describe the eyes of hagfishes.
What type of tooth structures do hagfishes possess in their mouth?
What type of tooth structures do hagfishes possess in their mouth?
What innervates the heart in lampreys?
What innervates the heart in lampreys?
How do lampreys regulate ions, water, and nitrogenous wastes?
How do lampreys regulate ions, water, and nitrogenous wastes?
What prevents water from flowing out of the respiratory tube into the mouth of lampreys?
What prevents water from flowing out of the respiratory tube into the mouth of lampreys?
How many pairs of gill pouches do lampreys have?
How many pairs of gill pouches do lampreys have?
What type of ventilation do adult lampreys use when they attach to other fishes?
What type of ventilation do adult lampreys use when they attach to other fishes?
Is the lampreys' mode of ventilation efficient at oxygen extraction?
Is the lampreys' mode of ventilation efficient at oxygen extraction?
What is the function of the oral hood in lampreys?
What is the function of the oral hood in lampreys?
Why is the tongue of lampreys not homologous with the tongue of gnathostomes?
Why is the tongue of lampreys not homologous with the tongue of gnathostomes?
What secretion from lampreys prevents the victim's blood from clotting?
What secretion from lampreys prevents the victim's blood from clotting?
What is the primary diet of adult lampreys?
What is the primary diet of adult lampreys?
Do lampreys generally kill their hosts?
Do lampreys generally kill their hosts?
What type of species are lampreys that have nonfeeding adults?
What type of species are lampreys that have nonfeeding adults?
Where are lampreys primarily found?
Where are lampreys primarily found?
What is the reproductive behavior of nearly all lampreys?
What is the reproductive behavior of nearly all lampreys?
What is the feeding pattern of some specialized lamprey species?
What is the feeding pattern of some specialized lamprey species?
When are adult lampreys generally observed?
When are adult lampreys generally observed?
What are lampreys known to attach to after swimmers' skin temperature drops?
What are lampreys known to attach to after swimmers' skin temperature drops?
What vertebrate group eventually replaces the notochord with well-developed centra as a supporting rod for axial muscles?
What vertebrate group eventually replaces the notochord with well-developed centra as a supporting rod for axial muscles?
Which two extinct groups of fishes did not have well-developed centra?
Which two extinct groups of fishes did not have well-developed centra?
What is the function of ribs in gnathostomes?
What is the function of ribs in gnathostomes?
In which group of reptiles and mammals are teeth set in sockets and held in place by periodontal ligaments?
In which group of reptiles and mammals are teeth set in sockets and held in place by periodontal ligaments?
What is the name given to the condition where teeth are fused to the jawbone, seen in most bony fishes and some reptiles?
What is the name given to the condition where teeth are fused to the jawbone, seen in most bony fishes and some reptiles?
What is the term for the supporting rod for axial muscles used in locomotion that is eventually replaced by well-developed centra in some vertebrates?
What is the term for the supporting rod for axial muscles used in locomotion that is eventually replaced by well-developed centra in some vertebrates?
What is the process by which lampreys construct their nest for breeding?
What is the process by which lampreys construct their nest for breeding?
How do lampreys ensure that the water in the nest is oxygenated?
How do lampreys ensure that the water in the nest is oxygenated?
What is the distinctive feature of lamprey larvae in terms of their appearance and behavior?
What is the distinctive feature of lamprey larvae in terms of their appearance and behavior?
How do lampreys reproduce, and what happens to adult lampreys after breeding?
How do lampreys reproduce, and what happens to adult lampreys after breeding?
What happens to lamprey larvae after hatching and leaving the nest?
What happens to lamprey larvae after hatching and leaving the nest?
How do lamprey larvae differ from their parents, and what is their initial genus name?
How do lamprey larvae differ from their parents, and what is their initial genus name?
Describe the implications of the gnathostome body plan in terms of activity and complexity.
Describe the implications of the gnathostome body plan in terms of activity and complexity.
Explain the significance of the variability of the gnathostome lower jaw in the Silurian period.
Explain the significance of the variability of the gnathostome lower jaw in the Silurian period.
Discuss the improvements seen in gnathostomes in terms of locomotor and predatory abilities.
Discuss the improvements seen in gnathostomes in terms of locomotor and predatory abilities.
Explain the evidence of a second Hox gene duplication event in living jawed vertebrates.
Explain the evidence of a second Hox gene duplication event in living jawed vertebrates.
Describe the role of extinct ostracoderms in the acquisition of features in gnathostomes.
Describe the role of extinct ostracoderms in the acquisition of features in gnathostomes.
Explain the impact of gene duplication on the complexity of animals.
Explain the impact of gene duplication on the complexity of animals.
What is the likely original function of jaws in early vertebrates, according to the text?
What is the likely original function of jaws in early vertebrates, according to the text?
What are some functions of jaws mentioned in the text other than predation?
What are some functions of jaws mentioned in the text other than predation?
When are gnathostomes first known with certainty, according to the text?
When are gnathostomes first known with certainty, according to the text?
What does the presence of isolated sharklike scales suggest about the origin of gnathostomes?
What does the presence of isolated sharklike scales suggest about the origin of gnathostomes?
What diverse behaviors involving jaws are mentioned in the text?
What diverse behaviors involving jaws are mentioned in the text?
What will be discussed later in the text regarding the likely origin of jaws?
What will be discussed later in the text regarding the likely origin of jaws?
What is the material that vertebrate jaws are made of?
What is the material that vertebrate jaws are made of?
In what head segment is the gnathostome jaw formed?
In what head segment is the gnathostome jaw formed?
How are the branchial arches related to the segments of the vertebrate head?
How are the branchial arches related to the segments of the vertebrate head?
What is the significance of envisioning the vertebrate head as a segmented structure?
What is the significance of envisioning the vertebrate head as a segmented structure?
Where do the more posterior branchial arches that form the gill supports originate?
Where do the more posterior branchial arches that form the gill supports originate?
What is the material that forms the hyoid arch jaw supports?
What is the material that forms the hyoid arch jaw supports?
