All the eggcitement of those deliciously decorated Easter eggs, got me pondering a little more on what eggstraordinary objects eggs actually are (sorry will try to restrict the egg puns!!) It seems I’m not alone in my ovum admiration, as would you believe that 99% of all living beings choose to reproduce by way of laying eggs!
The vast majority of living creatures lay eggs and have done so for millennium (I mean thousands of dinosaurs couldn’t’ve been wrong surely!) It’s really only mammals, along with a few snakes, reptiles and fish that give birth to live young instead.
It seems that eggs are an efficient way to bring the next generation into the world. It allows mum to produce her offspring as soon as possible, freeing her up to gather food and provide protection for her brood. Another benefit is that the new arrivals are cocooned in a protective outer coating, in which they can develop, shielded from the outside world, until they are ready to hatch.
There’s safety in numbers when it comes to egg laying, as typically greater quantities than are strictly needed are produced, allowing for some potential losses along the way.
Interestingly, there are a very few creatures who can’t seem to make up their minds on the eggs vs babies -some skinks can actually do both – laying both eggs and giving birth to live babies too! It’s thought this will help to give us some clues about the fact that eggs were the first chosen method of reproduction, with live birth arriving quite a bit further down the evolutionary track.
No self-respecting blog on eggs could skip mentioning the biggest and smallest specimens: no prizes for guessing that it’s the ostrich that wins the top slot here, with eggs weighing around 2.5kg (5lbs) and whilst that’s impressive, for an ostrich being the size it is, it’s actually one of the smallest in ratio to the size of its mum! Instead, spare a thought for the poor old kiwi, whose eggs are a whopping 6 times bigger than any others laid by birds of the same size – ouch!
Whilst you might be thinking that’s eggstraordinary (!), well how about the largest egg ever laid?! Now in ignorance, I was contemplating a dinosaur for this one, but I was wrong, because it was in fact the now extinct and aptly named Elephant Bird! This giant amongst fowl, was once a native of Madagascar – these huge, flightless birds, laid an egg that was 7 times bigger than the Ostrich’s!!! Holding an amazing 3.75litres (2 gallons) and weighing a hefty 10kg (22lbs)!!
On the other end of the scale, we come to what are surely the tiniest eggs, laid by a microscopic creature called a Rotifer, which can be as small as 0.05mm (0.001inch), so their eggs must be pretty minute!
When it comes to birds, the tiniest eggs here belong to the Bee Hummingbird, measuring a mere 7mm (0.275inches) and weighing a miniscule 0.025g (0.0009 ounces)!
Of course, not all eggs are the same: the word egg tends to make us think of birds’ eggs, which are typically hard shelled; however, many other creatures’ eggs are soft shelled eg turtle and crocodile eggs. As these don’t have the advantage of such a tough outer coating, mum will bury them for protection until they emerge.
One of the strangest looking eggs must belong to the shark – rather than that typically oval shape, sharks’ eggs are squarer and flatter and are commonly referred to as a mermaid’s purse.
If you thought that your painted Easter eggs were the brightest and best, well think on, because such natural creations as those of the American Robin or the Great Tinamou are naturally vibrant blue! Indeed, birds can go to great lengths to make their eggs blend in with their surroundings, an example of this is the Golden Plover, whose speckled eggs merge perfectly with their terrain, making it difficult for predators to spot them.
So, it seems that these ovoid creations are definitely an eggscellent way to bring along the next brood.