Dear watermelon,

You're light and sweet, and it's been nice hanging out with you over the summer. But the seasons are changing, and it's time I move on to pumpkins and squash.

Many of us have gone through these seasonal switches with plants of the cucurbitaceae family. Although bittersweet, the opportunity to appreciate their diversity wouldn't have been possible if it weren't for an event in plant evolution. About 100 million years ago, the genome of a single melonlike fruit copied itself. Over time, this one ancestor became a whole family of plants with different colors, shapes, sizes, defenses and flavors, such as pumpkins, squash, watermelons and cucumbers, according to a paper in the journal Molecular Biology and Evolution. The researchers compared the genomes and evolutionary trees of a number of plants including cucumbers, melons and gourds. Millions of years of environmental changes allowed the fruits to lose genes and tailor their own codes to become what we know them as today.

How terrifying teeth became bird beaks

Theropods, which included bloodthirsty killing-machines like the Tyrannosaurus rex and velociraptor, was once notorious for sharp, serrated teeth used to eviscerate prey and strip flesh clean from bones. But over millions of years, the fearsome beasts evolved into today's flamboyantly feathered birds, replacing their terrifying teeth with beaks. A study in the Proceedings of the National Academy of Sciences provides insight into a potential evolutionary mechanism behind the theropod's transformation. Using fossils and a large comparative analysis of modern animals, a team of evolutionary biologists found that the loss of teeth and the emergence of beaks are connected processes in theropods. As the beak grew across the dinosaur's face, it also inhibited the growth of teeth, the team suggested. On an evolutionary scale, this transition happened until theropods developed mouths that resembled the bird beaks seen today.

Observatory could top Pikes Peak

Astronomy enthusiasts are seeking permission to build an observatory atop Colorado's Pikes Peak. The National Space Science and Technology Institute based in Colorado Springs, Colo., recently submitted an application to the U.S. Forest Service. The Colorado Springs Gazette reports the proposal has faced one setback after another, including hesitation by government officials to allow new uses of the mountain. Supporters say the observatory would be the most heavily visited in the U.S.

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