Your Inner Reptile Flashcards
Do humans have a yolk sac? Do they make yolk?
Yes, humans have a yolk sac, but it doesn’t contain yolk
Mammals have hair, but reptiles have scales. In mammals, what might hair have been used for originally?
sensory perception and thermoregulation
Mammalian teeth are very different from reptilian teeth. What are the advantages and disadvantages of heterodont teeth?
Heterodont teeth allow for efficient processing of various foods through cutting, tearing, and grinding.
Disadvantages:
-The development of multiple tooth types requires more intricate genetic control, making them potentially more susceptible to developmental issue
-If teeth are not properly aligned, their specialized shapes can lead to malocclusion, affecting chewing function
-Loss of a single specialized tooth can significantly impact feeding ability compared to animals with uniform teeth.
Skin organs evolved from folded skin, which is partly controlled by the EDA gene. What skin organs are impacted by a dysfunctional (that is,
broken) EDA gene?
hair, teeth, nails, sweat glands, and/or skin
Reptiles have one middle ear bone, whereas mammals have three. Which bone is homologous between reptiles and mammals? From where did the
other two bones come in mammals? What are they called?
malleus and incus
I would argue that, technically, you don’t have an inner reptile. Why do you have an inner fish but not an inner reptile?
humans evolved from mammal-like creatures that came after the reptilian stage, meaning our most recent shared ancestor with reptiles is much further back in evolutionary history
What is a synapsid?
A synapsid is a type of amniote vertebrate characterized by a single opening in their skull behind each eye, which includes mammals and their extinct ancestors, often called “mammal-like reptiles”
What is a stem group?
a stem group refers to a collection of extinct species that are closely related to a living group (like mammals) but are not part of that living group itself
What is a crown clade?
a crown clade is a group consisting of all living members of a lineage and their most recent common ancestor, essentially defining the “current” version of a group in evolutionary terms.
