Friday, June 28, 2013

Glowing Scorpions

Photo credit: Cowyeow/Flickr

Scientists now believe that scorpions’ fluorescent exoskeletons may help them to find cover during the night.

The scorpion’s cyan-green glow can be attributed to two chemicals, noharmane and hymnecromone, that are deposited in the exoskeleton during sclerotization, a biological process by which arthropods are able to harden their exoskeletons. Interestingly, neither young nor recently molted adults fluoresce when exposed to UV light. Juvenile scorpions eventually develop the trait as they mature. Adults regain their fluorescence as their exoskeleton re-hardens as part of the molting process. In the picture below, you can also see that the scorpion’s old exoskeleton continues to fluoresce (Photo credit: skinheaddave/ 

Thursday, June 27, 2013

True or False???

Pollinators are important for the production of ~75% of the world’s leading crops, but honeybees are not the only insects responsible for providing these services.

The vanilla orchid can only be pollinated by a specific genus of solitary bee. Theobroma cacoa – the source of chocolate – is only pollinated by a tiny fly, and papaya flowers are pollinated by nocturnal sphinx moths. Bumblebees and solitary bees are also important for the production of a variety of other fruits and vegetables - squash and melons, tomatoes, blueberries, peppers, almonds, passion fruit, and brazil nuts, just to name a few.

If honeybees disappeared, food production would certainly suffer, but not all hope would be lost. Because the honeybee, Apis mellifera, is native to Europe and North Africa, many of the plant species that we now use as food crops did not evolve to depend on honeybees.

Although we still have much to learn about managing other types of bees, it is likely that, at least for some crops, alternative pollinators would be suitable replacements or even superior to honeybees. There are over 30,000 species of bees, with about 4,000 native to the United States alone, and a few species have already proven to be over 100 times as effective as honeybees.

So what would happen if we lost all pollinators?

Believe it or not, most of our food calories come from plants that don’t require animal pollination. Cereal crops like corn, wheat, and rice are wind pollinated. Many crops also come from non-reproductive plant parts like roots, stems, or leaves. Potatoes, carrots, beets, celery, broccoli, spinach, and cabbage are all examples of vegetables that can be produced without pollination. In these crops, pollination is only important for the production of seed for planting the next years crop.

Some crop types would be particularly sensitive to pollinator extinction. These plants are typically those that can’t self-pollinate and/or that require specific pollinators. Fruits like tomato, avocado, peach, coconut, mango, durian, and some vegetables fall into this category.

However, the largest effects of pollinator loss could be reflected in the production of coffee and chocolate, so there may be a reason to panic after all!

Mammals that chirp like crickets?!

Photo credit: Arto Hakola
Tenrecs are a family of mammals found in Madagascar and some parts of Africa.

Similar to the way that marsupials have diversified to fill a variety of ecological niches in Australia and New Guinea, tenrecs vary widely in body form and occupy a range of habitats. Some species have adopted otter-like forms, while others resemble shrews and hedgehogs.

The Highland and Lowland Streaked Tenrecs fall within the hedgehog type and are armed with barbed quills. These animals primarily feed on earthworms and take shelter in narrow burrows.

One interesting feature of the Streaked Tenrecs is that they are the only mammals known to communicate using stridulation. This type of communication is generally associated with insects and snakes, but although tenrecs lack wings and scales, they are still able to accomplish this using a second specialized type of quill that is arranged in rows along their back.  See a video here:

Even though tenrecs are sometimes hunted for food, the IUCN reports that Streaked Tenrecs are thriving and seem to be affected little by human disturbance:

You can learn more about Lowland Streaked Tenrecs here: