What gives birth to a puggle? Covered in spines, Australia's echidna is one of the rarest animals in the world: It's one of only two known mammals that lay eggs.

This walking, sniffing ball of spines is an echidna.

It's a mother on a mission.

She's hunting for ants and termites.

To find them underground or under wood, she uses her strong sense of smell and another weirder sense.

Studies suggest that special cells in her beak are sensitive to the electromagnetic signals emitted by all living things.

It's a sense usually found in sharks and rays, but the echidna may be the only land mammal that has the ability to search for food this way.

She's uncovered a colony of ants and uses her long sticky tongue to slurp them up.

She needs the nutrition.

She's already given birth...to an egg.

Echidnas, along with their cousin, the platypus, are the only egg-laying mammals in the world.

The egg incubates in a simple pouch under her belly.

Inside, a baby echidna, called a puggle, develops.

After about 10 days, the egg hatches.

The puggle stays inside the pouch, nursing from its mother's milk and packing on the ounces.

Two months later, the puggle starts to grow spines-that's its mother's cue to move it to a burrow, where she'll continue to take care of it for seven more months.

All that effort means a lot of food.

So her mission remains the same: find more to eat.