One of the coolest dinosaurs you learn about as a kid are Pterodactyls (really Pterosaurs, but who's checking). As giant flying lizards, these guys are thought to have dominated the skies long before birds existed (from the late Triassic to the end of the Cretaceous, 220–65 million years ago). The biggest of the bunch are Pteranodon and Quetzalcoatlus, which are thought to have weighed as much as 250 kg with wingspans in excess of 30 feet.But a new study, published in PLoS ONE is casting doubt on the ability of these massive winged dinos to actually fly. Instead, their results add to others which support these creatures as land animals who staked their prey, not swooping in to grab it.
In the study of flight, scientists generally believe that there is a "maximum size" that animals can be and still be able to fly. It has to do with competition between muscle power and power needed for flight. The heavier a creature is, the more force it must create with its wings to be able to lift that mass off the ground. However, muscles can only get so strong and bones can only resist so much force before breaking, causing there to be an maximum size limit, after which the animal is just unable to produce enough force. However, it's debatable exactly where this upper limit is because creatures use different wing shapes, sizes and flapping patters to achieve flight.
The extinct pterodactyls, though as big as a modern giraffe, have been compared in wing shape and presumed flight method to modern large birds like albatrosses, which are called procellariiforms. So researchers looked at how today's large birds are able to fly, and what kind of weight limits might exist for them.To see how the birds flew, they attached little acceleration data loggers attached to the birds wings to chart the flapping movements. They compared these data to the bird's weight, wingspan and wing surface area to see whether there was a correlation between how the birds flew and how big and heavy they were. They also took physiological measurements of the birds exertion during these behaviors.
They found that the birds used two types of flapping to fly: a high-frequency one to get off the ground and a low frequency one once in flight to maintain altitude. As predicted, both high and low flapping frequencies decreased according to the size of the bird, suggesting that at a certain weight, they simply could not flap their wings fast enough to attain lift off or maintain flight in the absence of wind. The researchers calculated that this weight limit was around 41 kg, which is about 1/2 of what the average large, ancient pterodactyls are thought to have weighed."Our study of living Procellariiformes as model animals suggests that if pterosaurs larger than 41 kg (or 5.1-m [>15 foot] wingspan) had the narrow wings, they could not have attained sustainable flight in environments similar to the present," write the authors in their concluding paragraph. They go on to add that "the results of the present study lend support to a recent reappraisal suggesting that large pterosaurs were terrestrial stalkers, finding much of their food via terrestrial, ground-level foraging."
In other words, the study authors suggest that the great flying dinosaurs actually couldn't fly, at least not well enough to use it as their main hunting technique. Instead, the Pterodactyls were grounded. They do note, however, that their data don't completely rule out the possibility of flight. Other conditions could have been different in the past, including a lot more wind and thermal updrafts (like the ones which fuel vulture flight). Even the air itself could have been denser, or gravity slightly weaker. So the majestic image of huge, flying Pterodactyls isn't an impossibility.None the less, the researchers do a pretty good job of destroying the fantasy dinosaur images of children everywhere by knocking the Pterodactyls out of the sky. Those flying monsters are the best part! And if they really didn't fly, well, dinosaurs just got a little less cool in my book.
Sato, K., Sakamoto, K., Watanuki, Y., Takahashi, A., Katsumata, N., Bost, C., & Weimerskirch, H. (2009). Scaling of Soaring Seabirds and Implications for Flight Abilities of Giant Pterosaurs PLoS ONE, 4 (4) DOI: 10.1371/journal.pone.0005400
If you're as appalled by the filth that we have thrown into our oceans, 
How was it, though, that I was so competent, able, and clear almost 18 hours after I got up in the morning? Scientists from the University of Liège might just have an answer. It turns out that people who self-describe as "night owls" instead of "early birds" maintain higher levels of attention and perform better on mental tasks as the evening wears on.
So the researchers designed an ingenius experiment to look at the value people place on rare animals. They set up a website allowing people to choose to download slideshows of various groups of animals. One slideshow was of rare species - the other of common ones, and they were randomly placed on the page. However, unbenounced to the participants, the slideshows never actually downloaded. Upon clicking the link to a slideshow, an upload progress bar opened, and the program began recording how long people were willing to wait for their images before giving up and canceling the download.
These results strongly support the idea that rare species, just by being rare, are valued more. This opens these endangered species to the possible damages of antropogenic Allee effects. As the authors write, "The particular threat this effect poses on rare species is sufficiently disturbing for conservationists to use caution when disclosing rarity, as well as to begin a dialogue about the measures that can be adopted to protect rare species from this new threat."
The image looks like a mustard plant with nice, yellow flowers. But alas! It is actually the product of this week's parasite, the rust fungus Puccinia monoica.
They then got another 120 adults to different levels of drunk and asked them the same questions. They found that the alcohol did have an effect on attractiveness - the more the participants drank, the hotter a mature girl got, if she was wearing make-up (but they found no effect of alcohol statistically on the attractiveness of immature faces or those without makeup). But one thing that didn't change was the men's ability to estimate age. There was no difference between the age of the photos as estimated by the sober and plastered men. As the authors write, "placed into its forensic context, this study tentatively concludes that alcohol consumption and make-up use do not interfere with age-perception tasks, nor inflate subsequent age estimates." So saying that anything makes a guy mistake 
Results like these bring into question the validity of "mistake of age" defenses, especially in cases of statutory rape where the accused is more than 10 years older than the minor. As long as a minor is at least two years younger than the consenting age, it's likely that guys know she's underage. The researchers also pointed out that other cues of age, like tone of voice or language use, aren't factored into this study, so it's possible that men's age estimates are even more accurate in the presence of these variables. At any rate, it seems the excuses for statutory rape are fading fast.
