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Why Are Calico Cats Almost Always Female (and Always Look Different)?

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There’s a reason that colorful cats, like tortoiseshells and calicos, tend to be female. It comes down to genetics. 

Females (of all sorts, not just cats) have two X chromosomes, while males have an X and a Y. Rather than being overwhelmed by the double dose of genes provided by having two X chromosomes—each carries more than 1,000 genes—lady organisms have developed something called X-chromosome inactivation, a process that effectively hits the mute button on one of the two X-chromosomes in a cell. 

Kat McGowan explains in Nautilus

On the X chromosome of cats is a skin- and fur-color gene that has two variations (alleles) that dictate either orange fur or black fur. If a female cat inherits one X chromosome with the black allele and one with the orange version, each cell will have both versions, but X-inactivation means that some of her skin cells will code for orange and some for black. The inactivation happens very early in development, when the cat-in-the-making is still just a ball of cells, and the particular nature of skin tissue is that cells and their progeny stay close together. One of those primordial skin progenitor cells that happens to have an active orange allele will give rise to a cohesive blob of millions of cells in the fully developed cat, forming a big orange blotch. The same is true for those coding for black. 

The donor cat (left) and resulting cloned kitten (right, with surrogate mother). Image Credit: Shin et al., Nature (2002)


No calico cat will ever look identical to another. The particular pattern of a multi-colored cat’s coat comes down to chance, meaning that even among the same family, no cat will have the same coloration. Even with the exact same genetic make-up, a calico cat’s coloration would be different than her twin’s because it’s random whether a cell codes for orange or black fur. The same goes for clones. In 2002, when scientists cloned a calico cat named Rainbow, the clone kitten had vastly different coloring from Rainbow, even though their genes were exactly the same. 

Because X-inactivation only happens if there are multiple X chromosomes in one cell, coloration patterns that stem from the process tend to only pop up in female cats. Rarely, a genetic mutation can result in a cat being born with an extra chromosome (XXY), leading to a male calico or tortoiseshell cat, but for the most part, it’s purely a ladies’ club. 

[h/t: Nautilus]

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Why Are Mugshots Made Public Before a Suspect is Convicted by the Court?
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Jennifer Ellis:

Several reasons.

1. Mugshots can help find people when they have absconded, or warn people when someone is out and dangerous. So there is a good reason to share some mugshots.

2. Our legal system requires openness as per the federal constitution, and I imagine most if not all state constitutions. As such, this sort of information is not considered private and can be shared. Any effort to keep mugshots private would result in lawsuits by the press and lay people. This would be under the First and Sixth Amendments as well as the various Freedom of Information Acts. However, in 2016 a federal court ruled [PDF] that federal mugshots are no longer routinely available under the federal FOIA.

This is partially in recognition of the damage that mugshots can do online. In its opinion, the court noted that “[a] disclosed booking photo casts a long, damaging shadow over the depicted individual.” The court specifically mentions websites that put mugshots online, in its analysis. “In fact, mugshot websites collect and display booking photos from decades-old arrests: BustedMugshots and JustMugshots, to name a couple.” Some states have passed or are looking to pass laws to prevent release of mugshots prior to conviction. New Jersey is one example.

a) As the federal court recognizes, and as we all know, the reality is that if your picture in a mugshot is out there, regardless of whether you were convicted, it can have an unfortunate impact on your life. In the old days, this wasn’t too much of a problem because it really wasn’t easy to find mugshots. Now, with companies allegedly seeking to extort people into paying to get their images off the web, it has become a serious problem. Those companies may get in trouble if it can be proved that they are working in concert, getting paid to take the picture off one site and then putting it on another. But that is rare. In most cases, the picture is just public data to which there is no right of privacy under the law.

b) The underlying purpose of publicity is to avoid the government charging people and abusing the authority to do so. It was believed that the publicity would help protect people. And it does when you have a country that likes to hide what it is up to. But, it also can cause harm in a modern society like ours, where such things end up on the web and can cause permanent damage. Unfortunately, it is a bit of a catch-22. We have the right to know issues and free speech rights smack up against privacy rights and serious damage of reputation for people who have not been convicted of a crime. The law will no doubt continue to shake out over the next few years as it struggles to catch up with the technology.

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

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What Happens When You Flush an Airplane Toilet?
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For millions of people, summer means an opportunity to hop on a plane and experience new and exciting sights, cultures, and food. It also means getting packed into a giant commercial aircraft and then wondering if you can make it to your next layover without submitting to the anxiety of using the onboard bathroom.

Roughly the size of an apartment pantry, these narrow facilities barely accommodate your outstretched knees; turbulence can make expelling waste a harrowing nightmare. Once you’ve successfully managed to complete the task and flush, what happens next?

Unlike our home toilets, planes can’t rely on water tanks to create passive suction to draw waste from the bowl. In addition to the expense of hauling hundreds of gallons of water, it’s impractical to leave standing water in an environment that shakes its contents like a snow globe. Originally, planes used an electronic pump system that moved waste along with a deodorizing liquid called Anotec. That method worked, but carrying the Anotec was undesirable for the same reasons as storing water: It raised fuel costs and added weight to the aircraft that could have been allocated for passengers. (Not surprisingly, airlines prefer to transport paying customers over blobs of poop.)

Beginning in the 1980s, planes used a pneumatic vacuum to suck liquids and solids down and away from the fixture. Once you hit the flush button, a valve at the bottom of the toilet opens, allowing the vacuum to siphon the contents out. (A nonstick coating similar to Teflon reduces the odds of any residue.) It travels to a storage tank near the back of the plane at high speeds, ready for ground crews to drain it once the airplane lands. The tank is then flushed out using a disinfectant.

If you’re also curious about timing your bathroom visit to avoid people waiting in line while you void, flight attendants say the best time to go is right after the captain turns off the seat belt sign and before drink service begins.

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