Echidnas have some of the most unusual biology you will come by. Here's a quick list of some fun facts. Stay tuned for more!
The echidna and their cousin the platypus are the world’s oldest mammals – they are almost 200 million years old!
Echidnas and platypuses are called monotremes. The word monotreme literally means ‘one hole’.
Monotremes are the only egg-laying mammals. The egg is only the size of a grape and the shell is very thin, fragile, and has a leathery texture.
Echidnas only breed during July-September every year, so that is the best time to spot them in the wild as they are most active.
Echidnas on Kangaroo Island are now listed as endangered.
Male echidnas have a four-headed penis.
Echidnas appear on our 5-cent coin. Baby echidnas are so small after they hatch from their egg that it would take 8 baby echidnas to weigh as much as a single 5-cent coin.
A baby echidna is called a puggle!
Some echidnas hibernate.
Unlike all other mammals that have 2 sex chromosomes (XX females, XY males), female echidnas have 10 sex chromosomes (10X) and males have 9 (5X4Y).
The spines of echidnas are just really thick hairs. They’re made out of keratin, which is the same as what our hair and fingernails are made of.
Echidnas’ hind feet point backwards. This is to help them dig better.
Echidnas have a lower body temperature than other mammals, resting at around 30 °C. Their body temperature can also fluctuate 6-8 °C during the day.
You can’t tell if an echidna is male or female by simply looking at them as they have no gender-specific features and their reproductive organs are internal.
All echidnas are born with spurs on their hind limbs, similar to what male platypuses have. They are not venomous like in platypus, but the glands underneath the spurs secrete pheromones used for attracting each other during breeding season. Females are meant to lose the spurs as they mature but some retain the spurs, while some males lose them.