This is one of the best reader photos I’ve ever posted, and it comes from photographer John Chardine.  He described the scene in his first email (all posted with permission):

I’ve been photographing a pair of Peregrine Falcons at a nest not far from home.

Right now there is a single chick in the nest. The (much smaller) male is hunting for birds—mainly American Robins—and is bringing them back plucked and usually without the head (which he eats). The interesting part of the story is that rather than bring them back to the nest, the male transfers the prey to the female in mid-air, and the female then takes the prey item back to the nest and feeds the chick. All this happens in 5 seconds ± so you have to be quick on the the camera trigger!

In the image the smaller male is above with the food item in its beak. The female is reaching up with her talons to grab the food item.

There is pronounced (reverse) sexual dimorphism in the Peregrine with the male much smaller than the female. When the chicks are young the parents only need to bring in small prey like robins and the male is supremely built to kill small birds. Peregrines capture their prey by diving on them at incredible speeds—the fastest in the bird world. Later on when the chicks get older, they need more food delivered per unit time and sometimes the larger female will step in taking larger prey like for example ducks and gulls. A big problem for flying predators like Peregrines is “payload mass”. They have to be able to carry back the prey (payload) and if it’s too heavy they can’t do it. Larger females can fly with bigger prey than the smaller males.

But why doesn’t the male just feed the small birds he catches directly to the chicks? Why does he hand them over to the female?

That’s a good question and I don’t know the answer. There are many options for what the male could do. The simplest might be to do what you suggest- bring back the prey and feed the chick. The next obvious option might be for the male to deliver the prey to the female at the nest and then she feeds the chick. This is known to occur in some pairs. What I can say is that immediately after the food exchange in mid-air we see the male fly away and we assume he is traveling to his “kill” location. There is no lost time in doing this, which may explain why he does not stick around and feed the chick. If he stayed, the most efficient system would be for the female to fly out to hunt, and that is indeed an option that probably occurs when the chick is old and requires bigger meals. To have both birds attending the nest- one feeding and one hanging around- is inefficient and indeed may not allow sufficient power delivery (energy per unit time) to the nest. It should be mentioned that feeding takes time as the parent has to tear apart the prey in appropriately small morsels for the chick. Currently, with a chick about 12 days old, a complete feeding may take 20-30 minutes.

by Matthew Cobb

Summer has officially begun in the northern hemisphere (you could have fooled me), so many of our birds will have finished rearing their young, but you still might find a baby bird on the ground.

This handy cut-out-and-keep piece of advice from birdandmoon.com tells you what to do:

h/t HPS_Vanessa

While we’re about it, here’s another piece of bird lore from birdandmoon – while evolution is most certainly true, it can also suck:

by Matthew Cobb

Last night NASA released this billion pixel image of the Martian landscape, from where Curiosity is sitting at the moment, in a place called Rocknest (it’s called that by NASA; we’re not sure what the indigenous inhabitants call it, what with them having a hundred words for ‘red rock’ and all).

Go on, click on that link and have fun. It’s astonishing – you will be investigating the surface of Mars from your earthbound desk, or even more amazing, a handheld device! We may not have jetpacks or flying cars, but the 21st century has certainly delivered on its promises here!

There are several different versions of the image, either a cylindrical one, or a straight zoomable/scrollable one. You may need Flash (grr) or Silverlight installed. Here’s what the opening page looks like:

And because the image is so dense, you find all sorts of weird things in there. Here’s something I noticed, which NASA has called a ‘white shiny object’. It’s to the left of Curiosity’s ‘head’, in the Panoramic viewer. See if you can find it. What is it?

And even weirder, this Martian bird, spotted by NASA in the sky about 15% in from the right:

And here’s something that really IS true. It’s a dry waterfall on Mars, spotted by the HI RISE satellite in the Southern Branch of Kasei Valles (there’s a stereo pair of these images, so if you follow the links you’ll be able to look at it in 3-D…):

by Matthew Cobb

In high desert of southwestern Wyoming in the USA there is a deserted town with the apt name of Fossil (pop: 5. Yes, 5). Around 52 million years ago, it was a subtropical lake surrounded by forests and lying in the shadow of a volcano. One of Jerry’s colleagues, Lance Grande of the fabulous Field Museum of Natural History in Chicago, has just published a beautifully-illustrated book on the amazing fossils to be found in the area, animals that were preserved at the bottom of the lake, and were then brought to light by the skill of paleontologists in an area now known as Fossil Butte, which is part of the famous Green River formation. Go look at it on Google Maps!

Here are just a few examples:

Two specimens of an extinct constrictor, Boavus idelmani. The bottom is the first fossil of this species, or ‘holotype’, which is now lost.

[JAC: Note the separate toes in the horse relative above: all but one of these toes would gradually disappear in the lineage leading to modern horses, leaving them with a single middle toe—otherwise known as the “hoof.” The vestigial remnants of two of the flanking toes can still be seen as the “splint bones” on the skeletons of modern horses.]

The book is published by University of Chicago Press (who else), and is entitled The Lost World of Fossil Lake: Snapshots from Deep Time. All photos here © Lance Grande

Here’s the fab cover. The book is out now, buy it from your local bookshop, who almost certainly pay their taxes and also need support!

The history of Fossil, and of the fossils, is tied up with the history of coal and of the railway which ran past the town and carried the coal. Miners were the first to dig out the fossils. The deserted railway depot is now being restored. You can see what the place looks like now, and the restoration work 52 million years after the  lake disappeared, in this YouTube video. These are our fossils: