ScienceBlogs.com is running “Ask a Science Blogger”. The basic idea is that you, the reader, get a chance to ask questions to us, the bloggers. You can either post a comment in the link above or send an email to .
I would like to go ahead and answer one of the questions already posted. nemski asks:
How big does the world appear to an insect?
I like this question because it can be answered at different levels. First, what do you mean by world? If you mean “the Earth”, then the answer would be that the Earth essentially appears the same to an insect as it does to us humans (from a size perspective). So, maybe you know the Earth is spherically shaped. However, we can’t really see the curvature of the Earth from the ground because it is so big. Essentially, the variations in the ground level are much greater than any effects due to the curvature. Now, if you get even closer to the surface of the Earth, the same is true. Both humans and insects would see the ground as looking “flat”. On a related note, check out Bad Astronomy’s post on how far away is the horizon.
But maybe this isn’t what the commenter meant by “world”. Maybe the commenter meant “how would things in a room look for an insect?” There is one aspect of this question that I am not going to address – how do insects’ eyes work compared to human eyes? I don’t know if I could explain this well enough. My strategy for deal with questions I can’t answer is to answer a different question. The question I will answer: if a human were the size of an insect, how big would things look. Maybe this was actually the intention of the question.
Insect Scale
I am going to say a human is 1.5 meters tall. How about an insect? Insects come in lots of different sizes. I am going to estimate an average size of about 2 millimeters tall (that seems like a normal large ant). So, in terms of height, the ratio of human to insect height is:
A human is about 750 times taller than an ant. Note, don’t confuse this with mass or volume. A human is way more than 750 times the volume of an ant. Ok. Suppose I am a human and I am standing 10 meters away from a 4 story building (about 12 meters tall). Here is a rough sketch.
Using some simple trig, this angle theta would be:
So what would look the same to an ant? I will assume that the ant would see something that has an angular height of 50 degrees. But, how far away would the ant have to be? The human was 10/1.5 = 6.7 human lengths away from the building. For an ant to be 6.7 ant lengths away from the object, this would be 6.7*2 mm = 13.2 mm away. So, using the same diagram above, theta is the same, but d = 13.2 mm – this would have an object of height:
I looked around for something about 1.5 cm tall on my desk. Here I took a picture of a marker on my desk. I also took a picture of our building.
