Maybe I make too much of such things but, here's what Oprah, the narrator just said. Well, something to the effect of: Every living thing needs energy. The ways it gets its energy are fascinating... [blah... blah]..."
As she is saying this cliche bit, they are showing a beautifully lit, perfectly shot (jealous!) Venus Flytrap snatching a fly. Argh!
Why does this make me mad? Well, the answer lies in the apparent conundrum: Why do carnivorous plants need to eat? They are green, and so supposedly photosynthetic. If they are able to 'make food from the sunlight,' what's with the elaborate mechanisms to catch poor insects with?
Photosynthesis is a series of chemical reactions that capture energy from the photons of light coming from the Sun into, mostly, a sugar molecule called Glucose. Glucose is not a very complicated chemical at all. It has six Carbons, six Oxygens and twelve Hydrogens (C6H12O6). These materials come from the Carbon Dioxide we breathe out and the water in soil (some of which we breathe out, too!)
So, where do the BUGS come in? The fairly simple individual chemical reactions that trap the Sun's energy into Glucose are all orchestrated by various proteins, hormones and enzymes (also proteins). Proteins are made out of strings of Amino Acids. Amino Acids have to have Nitrogen. Some have Phosphorus and Sulfur and other important nutrients, too.
Most plants get these nutrients from the soil through their roots. Most of the world's carnivorous plants live in bogs. A bog is a habitat made of a floating mat of Sphagnum Moss growing over slowly moving water. The substrate is acidic and holds very few of the nutrients plants need to make proteins. Venus Flytraps, Pitcher Plants, and Sundews need to capture insects and digest their proteins for these raw materials.
For all of the expertise and energy and *beautiful, amazing , incredible* videography they used to put together this series, something so simple shouldn't have been missed. They could have shown any predator eating any animal to make that point. But the Venus Flytrap was NOT capturing that fly for energy - it uses photosynthesis for that!
Maybe my standards are too high! I won't even go into the (personally offensive) cheap-o shortcut 'cold-blooded/warm-blooded' language ---- somebody help me here!