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A Purdue University study found that the commonly found German species of roaches are being born with an immunity to certain toxins. The study concluded the evolution of the Blattella germanica — described as “the species that gives all other cockroaches a bad name” — develops an immunity to new poisons in as quickly as one generation of offspring.

“We didn’t have a clue that something like that could happen this fast,” study co-author Michael Scharf said. “Cockroaches developing resistance to multiple classes of insecticides at once will make controlling these pests almost impossible with chemicals alone.”

Ancient hyena teeth offer clues to past

This past February, Jack Tseng examined a pair of million-year-old teeth at the Canadian Museum of Nature’s research facilities in Gatineau, Quebec. “Within 5 minutes, I could tell,” he said. These were the teeth of ancient hyenas — Chasmaporthetes, or “running hyenas,” known for their speed and endurance.

Although only four hyena species exist today, nearly 70 species are known to have once roamed the planet. But these teeth, identified in the journal Open Quaternary, provide the first evidence that hyenas also lived north of the Arctic Circle, suggesting that the hyenas crossed the Bering land bridge from Asia into North America, just as humans most likely did.

Watching galaxies as they are about to die

The beginning of the end of our galaxy is just a few billion years away. That’s when the glittering disk of the Milky Way is projected to smash into its nearest neighbor, a spiral galaxy called Andromeda. The force of the collision will fuse the black holes at the centers of the galaxies, producing a luminous whirlpool of fast-moving, ultrahot gas known as a quasar.

Quasars are prone to cataclysmic flashes, which sweep gas and dust — the stuff that suns and worlds and life are made of — straight out into the circumgalactic medium. Eventually, the galaxy will empty itself of the material for making new stars.

This is how galaxies die — at least, according to the theories. But until now, no one has captured a galaxy in its transition phase, after the formation of a quasar but before it has lost all its stellar building blocks.

In new research, astrophysicist Allison Kirkpatrick announced the detection of 22 objects she calls “cold quasars.” These bodies glow bright enough to be beginning their death throes, but still contain cool clouds of dust, suggesting that they haven’t yet lost the ability to birth new stars.

They are right on the brink — hovering between the epoch of creation and the eon of waiting for death. “One of the biggest questions we have in astronomy is: How do galaxies die?” she said. “We know what they look like once they’re dead … but the rest of it is just pieces that we’ve guessed at.”

Now, she said, “we’ve found a population that we can study in detail.”

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