Plants and animals occupy tiny twig on tree of life
This article in Harvard magazine explains that plants, animals and fungi are just a tiny part of the tree of life.
The modern “tree of life,” based on genetic analysis, shows that the bulk of Earth’s biodiversity resides among the Archaea, Bacteria, and that portion of the Eukarya that does not include plants, animals, and fungi.Link (Thanks, Thomas!)Scientists had known that there are more microbes in an ounce of soil than humans alive on Earth, but that was just a measure of abundance. Pace’s discovery demonstrated something new, a previously unfathomed repository of biodiversity. Scientists began sequencing DNA from all sorts of environments. After looking at human gut microflora, they learned that each individual has his or her own characteristic set of a thousand species. “These represent three million genes that you carry,” points out Kolter, “as compared to the estimated 18,000 genes of the human genome. So you are living and exchanging [metabolites] constantly with a diverse pool of some three million genes.” Microbiologists continue to find new taxonomic divisions of microbes far faster than they can figure out how to culture them.
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it would be interesting to see this graphic weighted by things other than number of species. like 'total biomass' (all of the ants weigh more than all of the other insects and all of the other animals combined) or 'length of dna' (lilies win in this category)(species often lengthen their dna as a defense mechanism against viruses...separating the viral dna from their own genes with long strands of nonsense). i wouldn't be surprised if the graphic changed significantly. (i also wouldn't be surprised if it stayed exactly the same)
The general importance of Us isn't going to change much; if you take all of Animalia and weight just the humans, just the vertebrates, just the deuterostomes, it comes out pretty much the same.
This graph is even cooler when you look at the shapes of the branches-- the prokaryotes have a lot more of that, which means a lot more ways of being.
Much of the same material is covered in Bill Bryson's Book "A Short History of Nearly Everything" chapter 20, "Small World". I highly recommend the book for general purposes, but especially this chapter. You'll never think of yourself as alone again, once you start to understand your relationship with the life that isn't you, that exists inside of you. As good as the Harvard article is, Bryson's writing style is much more engaging and entertaining.
And if you measure it by intelligence or influence on the world, we're the lion's share.
#2...yeah, but those 'different ways of being' are mostly just different metabolic cycles...not all that thrilling (to me anyway). but then i'm a eukaryotophile...all those bacterias look the same to me. ;)
#3...absolutely! we're a lot more of a community than we like to think about...i liked the part in this article about how our bacterial colonies are all different though...eeewww! i read this fascinating article once about this tiny nocturnal squid that lives in the shallow coastal waters of hawaii (in 'science spectra' magazine, i believe). the juveniles had these special siphons that would suck water through these 4 sacs on its underside until it picked up a particular, bioluminescent bacteria. then it would stop siphoning, the sacs would seal and it would breed these bacteria until they got all fat and glowy. ready for the cool part? these squid can contract these light organs behind their ink sac to shutter the amount of light released. why? so that no matter what the moon's phase is, they leave no shadow when hunting. cool, right? stealth squid! (plus they're only 4cm long when fully grown and are cute as buttons)
#4...i wouldn't be so sure. ahem... stealth squid!
That "tree of life" is pretty old now and gives the heebie-jeebies to anyone with a background in molecular phylogenetics. It is severely bent and biased by a number of pretty well-understood artifacts that arise from oversimplified tree-building methods.
The basic upshot is that all the short branches cluster together within each major group, and all the long branches hang out towards the middle. Consequently it looks like plants, animals, and fungi cluster at the tip of the radiation. There is a truckload of newer work that discredits this notion, though there are of course some old-school hangers-on who won't let it go.
A better look at the overall tree can be found here - http://www.tolweb.org/tree/
I'm not actually complaining about the bulk of the article, just that particular tree.
Does this really come as a surprise to anyone? If there's news here at all, it's just the empirical verification of what any worker with sound statistical instincts would have hypothesized in the first place, namely that as organisms become less structurally sophisticated they become more diverse as well as more ubiquitous--arguments from entropy and energy, respectively.