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Monday, February 1, 2016

Where Do Killer Meteorites Come From?

I was browsing through social media when I came across someone asking an intriguing question:
How do meteors leave the asteroid belt?

This question brought to mind a science story I knew – about the asteroid that killed the dinosaurs.

I'll get to that, but first, a sub-question: do meteors even come from the asteroid belt?

Tuesday, January 19, 2016

Why Were Prehistoric Animals So Big?

The other day I stopped by the American Museum of Natural History to visit their newest dinosaur display: the Titanosaur!

Discovered just last year in Argentina, this new species hasn’t officially received a name yet, but it is one of the largest dinosaurs yet discovered – the museum reconstruction is 122 feet long – and a lot of the skeleton has been uncovered between several specimens, unlike most poorly-known large sauropods.

The new titanosaur mount at the AMNH,
Photo by me, standing directly under the tip of the tail.
The media-hype over this skeleton, and the recent scientific reports about massive ancient giraffes and giant marine crocodiles, has a lot of people revisiting an old question: why were prehistoric animals so much bigger than their modern-day relatives?

Tuesday, January 5, 2016

Have You Seen "Prehistoric Beast?"

I only recently learned of a short film from 1984 called Prehistoric Beast.

Wait, don’t Google it yet!  Let me give you some backstory.

Dinosaurs have been a consistent feature of movies for almost as long as there have been movies. And they've played some pretty major roles in cinema history: the first well-known animated film character was a dinosaur; some of the most iconic early stop-motion animation was done with dinosaurs; and one of the most successful and recognizable movie characters of all time is a dinosaur, just to give some examples. 

Monday, March 2, 2015

Dawn Comes to Ceres

This Friday is going to be an exciting day in space exploration!

I just got finished watching NASA’s JPL briefing on the status of the Dawn spacecraft mission, and I loved it! And as Bill Nye says: “When you’re in love, you want to tell the world!”

The Dawn spacecraft was launched in September 2007, and in 2011 it became the first spacecraft to orbit a body in the main asteroid belt: it spent over a year examining the giant asteroid Vesta, making wonderful observations about its surface features and geologic activity. Vesta is the second-largest object in the asteroid belt, but Dawn wasn’t quite satisfied with that.

On Friday, it will reach Ceres, the largest object in the asteroid belt, and earn two other unprecedented titles: the first spacecraft to orbit two different worlds, and the first spacecraft to reach and investigate a dwarf planet.

Tuesday, January 13, 2015

Happy Accidents: Beneficial Mutations in Humans

A while back, I was talking with a group of young students about evolution and natural selection, and I was teaching them about the role of mutations when I was asked an interesting question that I failed to answer.

The concept of mutations can be tough to grasp, because mutation sounds like a really bad thing, and indeed it often is. A mutation is essentially an accident in your DNA, and while most of them are harmless, most of the rest have unfortunate side effects. And yet mutation is one of the driving forces of evolution: natural selection weeds out the bad accidents and encourages the good ones, and life changes through the generations.

Which brings me to this question I was asked: Are there examples of good mutations in humans?