Animalia Flashcards
What are the 3 subclasses of mamamals?
Monotremes, Metatherians (inc. marsupials) and Eutherians (inc. placentals)
What clade do mammals belong to (starts with S)?
Synapsids
In what period was the origin of pelycosaurs and therapsids?
Permian
In what period was the radiation of Mesozoic mammals?
Middle/ Late Triassic
What are pelycosaurs also known as?
Sail backs
What are the 3 classes on mammalian synapsids?
pelycosaurs, therapsids, cynodont therapsids (in order of derivedness)
Name 3 traits what evolved in synapsids
Dual gait locomotion; teeth specialisation; larger temporal fenestre, diaphragm, heat regulation improved
Name 5 features of the earliest mammals
Tiny; derived skull (larger brain and inner ear); lactation adn suckling; hair; special harderian gland (insulates fur)
What prompted the tertiary radiation of mammals?
potentially extinction of the dinosaurs
Why is high level homeostasis important fro reproduction?
SA:Vol ratio too large and not enough time fro brain development to control systems in juveniles
What is the major advantage of lactation?
Reproduce at any time of year
What did lactation facilitate in terms of teeth?
differentiation of teeth types; shift to diphodonty as don’t need continuous replacement
What is diphodonty?
two successive sets of teeth, initially the “deciduous” set and consecutively the “permanent” set
What did milk likely first evolve for?
Antimicrobial and immunity
What are the 3 main forms of mammalian locomotion?
Non-cursorial, cursorial, fossorial
What is unique about reproduction in monotreme?
Eggs can grow!
What are 3 strange traits of platapus?
1- A genome with good immune system with lots of natural killer receptor proteins
2- Venom- males have venomous spurs on heels of hindlegs
3- Electrolocation
Whats important about marsupalia milk?
Changes composition over time with development
What trait allows marsupialia embryos to suckle during devlopment?
Girdle
What is the name of the mechanoreceptive organs on star nosed mole nose?
Elmers organs; innervated by infraorbital nerve
What is the name for the sensors in harbour seals used to track hydrodynamic fish tracks?
Vibrissae
What adaptation do moths have to bat echolocation?
Some moths can hear clicks of bats and Aartiid moths can produce own sound to disturb the bats radar
How do Aartiid moths produce their own sounds to disrupt the bats radar?
Using tymbal organ on the metathorax
What are the 2 staged=s in Cnideria lifecycle?
Medusa and polyp
What are porifera?
sponges
What are ctenophora?
very diverse
How do placazoa feed?
graze
how do cnideria feed?
predators- sting