Monotremes. Flashcards
Platypus & Echidna.
What subclass of mammals are monotremes placed into?
Prototheria.
When did monotremes diverge?
BQ: Can you name the Epoch?
205 million years ago
BQ: Triassic.
Name 3 characteristics.
- They lay and incubate eggs.
- Feed via a milk patch, not a nipple.
- Endothermy not highly developed (bad a regulating their own heat internally).
What does the word ‘monotremata’ mean?
BQ: Why is this?
Monos - alone.
Trema - hole.
BQ: refers to cloaca.
Name the 2 families within the subclass prototheria.
- Tachyglossidae - echidnas.
- Ornithorhynchidae - duck-billed platypus.
Name the 2 generas within Tachyglossidae.
- Tachyglossus - short-beaked echidnas.
- Zagolossus - long-beaked echidna.
Name the singular species of ornithorhynchidae.
Ornithorhynchus anatinus.
Where are short-nosed echindas (Tachyglossidae) found?
Australia.
Tasmania.
New Guinea.
Where are long-nosed echidnas (Ornithorhynchidae) found?
New Guinea.
Where are duck-billed platypus (Ornithorhynchus anatinus) found?
Eastern Australia.
What group do we belive monotremes (prototherians) evolved from?
BQ: Within which branch of mammals?
a Mesozoic group.
BQ: Non-therian.
Name 6 characteristics of monotreme (prototheria) skull morphology.
BQ: which word describes the lack of teeth?
- Superficially bird like.
- The elongated rostrum is coverd by a leathery sheath.
- Lacramal bones absent.
- Jugal bones = small or absent.
- No auditory bulla.
- Adults lack teeth.
BQ: Edentate.
Name 3 characteristics of Prototherian skeletal morphology.
BQ: Name a skeletal characteristic specific to the short-nosed echidna.
- Shoulder gridle similar to reptiles.
- Pelvic gridle similar to marsupials.
- Limb posture suwhat similar to reptiles.
BQ: The humerous remals roughly horisontal to the substrate when walking.
What uniqueability do monotremes (prototherians) possess for hunting prey?
BQ: What does this allow them to do?
Electrical Pray-Sensing.
BQ: Electrical receptors detect electrical fields (small electrical impulses made by muscles of pray).
Name an anti-predation adaptation.
BQ: What is different in male platypi?
Male monotremes have a grooved erectile spine/claw.
BQ: Male platypus feed venom into the spine via a gland in their thigh.
Describe the penis and testies.
Bifurcate at tip (two halves).
Testies are eternal.
Ornithirynchidae.
Name 5 characteristics linked to being semiaquatic.
- Small eyes and pinna (located in a groove on the head).
- Large, hairless and rubber beak.
- 5 webbed toes (webs folded back when walking or burrowing).
- Dorso-ventrally flattened tail.
- streamlined body, covered in dense waterproof fur.
Ornithirynchidae.
Describe duck-billed platypus dentition.
Lack of teeth.
Horny grining pads/plates to crush prey.
Ornithirynchidae.
What does the duck-billed platypus eat?
Aquatic invertebrates.
Some plants.
Ornithirynchidae.
Describe the duck billed platypus reproductive behaviour.
Male chases female in water.
Each grabs the tail of mate and swims in slow circle.
Repeated for several days until they copulate.
Female lays 1-3 eggs in a burrow lined with leaves and grass.
Eggs are incubated for 10-11 days.
young feed on milk from a ventral milk patch.
Ornithirynchidae.
Describe their habitat.
Streams
Rivers
Lakes
Ornithirynchidae.
What is the platypus status?
Not threatened.
Ornithirynchidae.
What ecological niches/roles do they fill?
Important role in the food chain:
Feeding on freshwater invertebrates.
Providing food for predators.
Tachyglossidae.
What does Tachyglossidae mean?
Tachy - fast/swift.
glossi - tongue.
Tachyglossidae.
Describe the humerous of zagolossus.
BQ: What are they adapted for?
Broad extentions of the lateral and medial epicondyles.
Provide large surface for attachment of muscle.
BQ: digging.
Tachyglossidae.
Desctibe 4 characteristics of Tachyglossidae morphology.
- limbs are short and powerful - adapted for digging.
- spines are heavy and sharp, dispersed throughout dense coat of hair 9longer hairs on spine free ventral surface.
- Toes have powerful curved claws.
- Males have adapted spurs on their ankles (anti-predator defence).
Tachyglossidae.
Describe the diet of tachyglossus.
Ants.
Termites.
Tachyglossidae.
Describe the diet of zagolossus.
Ants.
Termites.
Earthworms.
Soil athropods.
Tachyglossidae.
Describe echidna dentition.
Lack teeth.
rows of horny barbs on their tongue and along the roof of their mouth.
Tachyglossidae.
Name 2 anti-predation adaptations.
- Roll into a ball (spines outwards).
- Burrow into the ground - leaving spiny surface exposed.
Tachyglossidae.
Describe their breeding behaviours.
Females secrete a strong smelling liquid, that is detected by males (pheramones).
Up to a dozen males follow the female for up to a month.
Female digs fore-legs into the ground, leaving her body slightly up-ended.
Males dig a trench around the female.
Males then fight, butting all but the winner from the trench.
Winner digs down beside the female and mates (either backwards or forwards.
Inserting bifucate penis into her cloaca.
Female lays a singular egg 3-4 weeks after mating.
The egg is incubated in a temporary pouch.
Puggles suckle from two milk lobules.
Tachyglossidae.
What habitat/s are tachyglossus found?
Open scurb.
Tachyglossidae.
What habitat/s are zagolossus.
Forest.
