Month: February 2011 (Page 4 of 6)

Bug of the Week: Fruit Flies

It is cold and windy this morning. The only insects that are still active are the fruit flies in the compost heap.

Why are they still active?  Probably because the rotting compost gives off heat. It is the warmest place in the yard.

Fruit flies of the genus Drosophila are easy to identify because of their bright red eyes.

You might also recognize that the white crawly things are the fruit fly larvae. (Photo by RickP at Wikimedia)

What are not so easy to identify are these funny little brown objects.

Those are the fruit fly pupae. The larvae change into pupae, usually after crawling out of the food to a drier location. Adults emerge from the pupae.

It is appropriate to honor the fruit fly here at Growing With Science. The humble fruit fly have been been the backbone of scientific work on genetics and developmental biology for over a century. Way to go, fruit flies!

Have you ever used fruit flies for a science project?

Mystery Seed of the Week 57

This week’s mystery seeds are also black, and seem to have two marks. They are about the size of a watermelon seed.

I found these on the ground at a gourd show, but the plants they grow into are not gourds. Can you guess what fascinating plant these seeds are from?

Edit:  The answer is now posted.

Seed of the Week: Catnip

We found the seeds for mystery seed last week in an unusual place. I noticed that the dried catnip (Nepeta cataria) we had purchased looked like it contained some flower calyxes.

The calyx is a tube-shaped structure formed from the sepals around the bottom of the flower. Curious, I tore open some of the brown ones (I assumed those were more mature) and sure enough there were seeds inside.

The seeds were in a cluster. As you can see from this painting by Jacob Sturm from 1796, the seeds are known to have two white marks.

(Image was downloaded from Wikipedia)

Catnip plants belong to the mint family, and thus have the characteristic square-shaped stem. They are originally from Europe, but were carried to North America by colonists (probably with their cats 🙂 ). Now they readily grow wild from seed and can be considered to be a weed.

The plants get their name from the fact that many cats find the plants attractive, like this one that rolled in the dried catnip I had set out to photograph. Scientists have discovered a chemical in the plant, nepetalactone, is what attracts the cats. The same chemical is a proven insect repellent. Guess that cat won’t have fleas or mosquitoes now.

The next step is to find out whether the dried seeds are still viable.

Have you ever grown catnip? Does your cat like catnip?

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