Newest members of the planet's team

It's February, but still not too late to welcome the newest members of our planet's team. They've actually been here for millennia, but we hadn't found them yet!

They are the thousands of new species discovered in 2013. We don't know exactly how many, since it may take months for scientists to determine whether each claim is valid or not. For now, have a look at these new team members:

At fullback: the olinguito, a relative of the raccoon who might just win the cutest new species award photo: Mark Gurney

Playing midfield, this teeny frog is the new world's smallest vertebrate - no name yet, but s/he can turn on a dime photo: Christopher C. Austin

On average, scientists describe 18,000 new species each year. They have confirmed 19,232 for 2009, the most recent year with a full confirmed assessment, and about half of these were insects.

What makes something a new species? The tried and true definition is a group of living organisms (plants, animals, protozoans) that can interbreed - that is, produce young that could go on to breed successfully themselves. (A mule is a cross between a female horse and a male donkey - they can interbreed, but mules can't reproduce successfully).

At left wing: the Cape Melville leaf-tailed gecko (check out that tail, plus fast feet help too!) photo: Conrad Hoskin.

Tending goal (calm under pressure, not falling asleep!), the lesula monkey, who looks uncannily human photo: Maurice Emetshu

The number of species in nature is not distributed equally across the globe. Some places, mostly in the tropics, have many more species than others. Some places have already been well-studied, while others are still poorly inventoried.

For example, the United States has 784 bird species and nearly 18,500 plant species, while Peru, which is 7.5 times smaller in area but is in the tropics, has over 1,700 bird species and 25,000 plant species.

A single 2012 National Geographic expedition to southeastern Suriname (northern South America for the geographically-challenged) found 60 species new to science. In other words, the biological diversity of tropical regions tends to be greater -- more ecosystems, more species, and more genetic variation -- than places farther from the Equator.

Here and here are additional links to new species discovered or described in 2013. They include a new porcupine, tapir, snails, many invertebrates, and fishes, including the bamboo shark, or walking shark (remember him?), below:

Our center forward: the walking shark, soon to be famous for his sneak attack on goal photo: Mark Erdmann

The right-winger: a Laotian giant flying squirrel - over 1m (42 in) long, scaring the you-know-what out of the opponents photo: Daosavanh Sanamxay

Do you have any new favorites you'd like to add?

Each species has different strengths – speed, agility, cunning – that allow it to adapt to and thrive in its habitat. I, for one, am happy to be a part of such an amazingly diverse team!