Agricultural Ants

     Imagine just for a second that someone dropped you in the middle of the rainforest with no directions, no food, nothing. How would you find your way out or even find something to eat? There might be some edible things nearby, but once you set off who knows when you'll find food again. Now imagine you were an ant on the rainforest floor. It would seem even bigger and be even harder to find food. There doesn’t appear to be many options; you could stay in one place and starve after you run out of food, you could set out and hope you stumble upon a new source of food, or you could…start a farm?
     Well, that’s what the ant species Atta cephalotes did. It may seem hard to believe but they actually beat humans to agriculture by about 50 million years. Just as the development of agriculture lead to a more stable food supply for humans, these ants ensure they will have something to eat by "farming" fungi. Agriculture allowed humans to stay in one place for a much longer period of time before their resources were exhausted and the same is true of these farming ants. Instead of spending huge quantities of time foraging for food (while under threat of predators), these ants spend time cultivating fungi to eat.

      I’ve given you the what and the why, so now for the how. While humans are sweating in the garden pulling weeds by hand or choking on pesticides, ants actually secret a substance which kills weed molds that have invaded their crops. Along with weeding, these ants also fertilize their fungi to increase their harvest. New research has also found that fungi-growing ants have updated their crops over time. DNA analysis has shown that one species of these ants dates back 12 million years while the fungus they grow is from just 2-3 million years ago. This evidence shows that these ants update their crops over time for maximum benefit, just as humans have done.

Why Do Penguins Have Wings if They Don't Fly?

     Although they can get some "air" when coming to shore or swimming at high speeds, penguins can't fly in the way we traditionally think of birds flying. But even though they can't soar through the air, they put their wings to good use when they're in the water. I think the author of the article in Science Now says it best: "Penguins can't fly, but don't feel sorry for them." They use their wings to propel themselves through the water, diving for up to 7 minutes and to depths of 300 meters!
     Paleontologists have been examining penguin fossils to determine what the ancestors of today's penguins looked like and how their swimming capabilities developed in a group of animals distinguished by flight. Julia Clarke and her team found a complete fossil dating back almost 36 million years ago. Clarke's team determined that this species of penguin (Inkayacu paracasensis) probably wasn't able to dive like modern penguins but that it was able to swim on the surface. Melanosomes, which are cells containing the naturally occurring pigment, melanin, are preserved in fossils. This allows researchers to determine the color of the animal in question. After examining the melanosomes from the fossil, the team determined this penguin most likely had gray or reddish-brown feathers. This may not seem like a big deal, but having black or dark brown wings is an advantage to penguins. The darker coloration occurs with higher concentrations of melanin which may also increase the strength and rigidity of penguin's wings. It appears as though having more melanin is at least one of the adaptations allowing penguins to become the skilled swimmers they are. However, one expert wonders why penguins aren't completely black if melanin is such an advantage. Another says that the black on white coloration provides camouflage. Perhaps this coloration gives penguins the "best of both worlds" so-to-speak; they have the strength of melanin as well as a white underbelly that is less distinguishable to predators in the depths. What do you think?

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I tried not to use too much jargon or uncommon words to keep the flow of the article going and also to prevent readers from becoming frustrated or confused. I included pictures to break up the wall of text; I know that I am much more likely to read something if there is a picture. I tried to "arouse and fulfill" by having a question as the title of my post, in the hope that readers would then want to learn more about penguins and their wings. I also tried to stay in active voice and explain things with enough, but not too much detail.