What's the Difference Between an Emu and an Ostrich?

An emu smiles for the camera.
An emu smiles for the camera.
iStock/hypergurl via Getty Images

Serge Elia:

Ostriches (below) and emus (above) are both members of the ratite group of large, flightless birds that are scattered throughout the Southern Hemisphere, including Africa (the ostrich’s range) and Australia (the emu’s range).

The two animals share many physical characteristics, such as broad eyes; an elongated, featherless neck; long, strong legs that burst into explosive speeds when on the run; long, dagger-like claws at the end of their feet (which they use vigorously to defend themselves); underdeveloped breast muscles; retrogressed flight feathers; and prominent wings that are used not for flight, but for courtship. Additionally, the males and females of both species are polygamous, and their eggs’ shells have a thickness so great that the hatchlings develop more rapidly than any other bird.

A female ostrich struts her stuff in South Africa
A female ostrich struts her stuff in South Africa's Kalahari desert.
EcoPic/iStock via Getty Images

But the two birds also have differences in terms of size, ecology, and behavior. Although emus are the largest birds in Australia (weighing around 80 to 90 pounds apiece), they're considered pretty small when compared to a fully grown ostrich, which is the largest bird on Earth (they're about three times the size of an emu, weighing around 220 to 265 pounds). While emus are mostly omnivores, feeding on plants as well as invertebrates like spiders and scorpions, ostriches tend to develop a strictly herbivorous diet (though they may eat insects).

Moreover, emus have three toes on their feet while ostriches possess two toes plus a long tendon that allows them to run at speeds of up to nearly 45 mph, whereas emus generally top out at 30 mph. Lastly, the emu is sometimes considered more docile toward humans than the ostrich.

Still, despite their differences, emus and ostriches do have similarities, and so they remain tangentially related to each other, since they are both flightless birds that are part of the ratite group as mentioned earlier. Which practically makes them cousins.

This post originally appeared on Quora. Click here to view.

What's the Difference Between Stuffing and Dressing?

iStock
iStock

For carbohydrate lovers, nothing completes a Thanksgiving meal quite like stuffing—shovelfuls of bread, celery, mushrooms, and other ingredients that complement all of that turkey protein.

Some people don’t say stuffing, though. They say dressing. In these calamitous times, knowing how to properly refer to the giant glob of insulin-spiking bread seems necessary. So what's the difference?

Let’s dismiss one theory off the bat: Dressing and stuffing do not correlate with how the side dish is prepared. A turkey can be stuffed with dressing, and stuffing can be served in a casserole dish. Whether it’s ever seen the inside of a bird is irrelevant, and anyone who tells you otherwise is wrong and should be met with suspicion, if not outright derision.

The terms are actually separated due to regional dialects. Dressing seems to be the favored descriptor for southern states like Mississippi, Tennessee, South Carolina, and Georgia, while stuffing is preferred by Maine, New York, and other northern areas. (Some parts of Pennsylvania call it filling, which is a bit too on the nose, but to each their own.)

If stuffing stemmed from the common practice of filling a turkey with carbs, why the division? According to HuffPost, it may have been because Southerners considered the word stuffing impolite, and therefore never embraced it.

While you should experience no material difference in asking for stuffing or dressing, when visiting relatives it might be helpful to keep to their regionally-preferred word to avoid confusion. Enjoy stuffing yourselves.

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Why Do Tires Have to Be Filled With Air?

BookyBuggy/iStock via Getty Images
BookyBuggy/iStock via Getty Images

Paul Misencik:

This is an issue that has perplexed me for most of my life, because pneumatic tires filled with air seem like the last anachronistic, 19th-century component of a modern automobile, and an idea which should have disappeared many decades ago. In an era where even the internal combustion engine itself is giving way to electric motors, and where a new economy hatchback has exponentially more computing power than the Space Shuttle, pneumatic tires don’t seem to make sense any longer.

(And before I get flamed, I know modern tires are vastly more advanced and reliable and capable than their 1930s counterparts. Blowouts, which were a common occurrence when I was a kid, are pretty much unheard of today. Modern tires are great, but they are still vulnerable and maintenance-intensive in a way that doesn’t make any sense to me.)

Companies have experimented with non-pneumatic passenger vehicle tires in the modern age—one of the primary drivers was Michelin. But the tires weren’t filled with solid rubber. In fact, they didn’t even have sidewalls. They were open on the sides, and they had a support lattice of structural polyester ribs, with a ton of air space between the contact patch and the (now deformable) wheel.

One of the big problems with switching from pneumatic tires to non-pneumatic tires is the fact that the current air-filled tire is an important component of the suspension of a vehicle. The flex in the sidewall is a critical part of the compliance of the suspension and substantially affects a vehicle's ride and handling. (Which is why race car drivers sweat tire pressures at each corner of the vehicle so much, as even a small change in tire pressure can have a big effect on the handling and grip of a vehicle.)

If a company like Michelin wants to make a non-pneumatic tire, they'll improve their chances of finding success with it if the new design mimics the compliance and flex characteristics of the outgoing, air-filled models as closely as possible. That way, Michelin would be able to sell the new, non-pneumatic design as a retrofit to older vehicles whose suspensions were originally designed with pneumatic tires in mind. And that is hugely important because if they can’t, it becomes much more difficult to convince manufacturers to change over to the new design—particularly after the mild debacle of Michelin’s failed “TRX” metric tire idea of the 1980s, which required the use of a special wheel and which, despite being by most accounts a superior design in almost every way, never really took off. (Owners of 1980s Ferrari 512 Berlinetta Boxers and some Saab 900 turbos will know what I’m talking about here.)

Non-pneumatic Michelin tires are also rather weird looking, and it’s not clear which manufacturers, if any, would take the risk of being the first to offer them on a new car.

So that is the real issue: Any non-pneumatic tire design must be not only clearly superior to the pneumatic designs of the past, but it must be functionally identical to the outgoing models they would replace, and they must be visually acceptable to consumers.

I hope it happens, though. I hope someone cracks the nut. Pneumatic tires are a 19th-century application still being used on 21st-century vehicles, and at some point that needs to change.

This post originally appeared on Quora. Click here to view.

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