Researchers were trying to discover why some types of organisms are incredibly successful while others didn't diversify all that much. We're quite sure you will just love the title for the study. (Science Daily: How to be winner in the game of evolution)
Please to try to relax on the groaning and then we can get on with this.
All animal species are divided among roughly 30 phyla, but these phyla differ dramatically in how many species they contain, from a single species to more than 1.2 million in the case of insects and their kin. Animals have incredible variation in their body shapes and ways of life, including the plant-like, immobile marine sponges that lack heads, eyes, limbs and complex organs, parasitic worms that live inside other organisms (e.g. nematodes, platyhelminths), and phyla with eyes, skeletons, limbs and complex organs that dominate the land in terms of species numbers (arthropods) and body size (chordates).
Amidst this dazzling array of life forms, one question has remained as elusive as it is obvious: why is it that some groups on the evolutionary tree of animals have branched into a dizzying thicket of species while others split into a mere handful and called it a day?
- SD
There's the problem to solve so we're interested to see what kind of an answer they find for it.
Jezkova and Wiens found that just three traits explained most variation in diversification and species numbers among phyla: the most successful phyla have a skeleton (either internal or external), live on land (instead of in the ocean), and parasitize other organisms. Other traits, including those that might seem more dramatic, had surprisingly little impact on diversification and species numbers: evolutionary accomplishments such as having a head, limbs, and complex organ systems for circulation and digestion don't seem to be primary accessories in the evolutionary "dress for success."
- SD
Oh, good. A key indicator for evolutionary success is to be a parasite.
Ed: I hope this is not an intro to anything political
Nah, I'm just curious about the science.
"We tested all these unique traits individually," Wiens explained, "for example, having a head, having eyes, where the species in a phylum tend to live, whether they reproduce sexually or asexually, whether they undergo metamorphosis or not; and from that we picked six traits that each had a strong effect on their own. We then fed those six traits into a multiple regression model. And then we asked, 'what combination of traits explains the most variation without including any unnecessary variables?' -- and from that we could reduce it down to three key variables."
- SD
There's the case for how they got down to the variables and maybe you'll have to take the validity of statistical analysis on faith but they know the language and result is novel.
The paper includes further analysis regarding the consequences of human behavior regarding animal extinction and you're invited to continue with the article on the link.
Make what you will of their conclusions about parasitism and we will skip any editorials / sci fi extensions of that but do have a ball on your own with it.
Please to try to relax on the groaning and then we can get on with this.
All animal species are divided among roughly 30 phyla, but these phyla differ dramatically in how many species they contain, from a single species to more than 1.2 million in the case of insects and their kin. Animals have incredible variation in their body shapes and ways of life, including the plant-like, immobile marine sponges that lack heads, eyes, limbs and complex organs, parasitic worms that live inside other organisms (e.g. nematodes, platyhelminths), and phyla with eyes, skeletons, limbs and complex organs that dominate the land in terms of species numbers (arthropods) and body size (chordates).
Amidst this dazzling array of life forms, one question has remained as elusive as it is obvious: why is it that some groups on the evolutionary tree of animals have branched into a dizzying thicket of species while others split into a mere handful and called it a day?
- SD
There's the problem to solve so we're interested to see what kind of an answer they find for it.
Jezkova and Wiens found that just three traits explained most variation in diversification and species numbers among phyla: the most successful phyla have a skeleton (either internal or external), live on land (instead of in the ocean), and parasitize other organisms. Other traits, including those that might seem more dramatic, had surprisingly little impact on diversification and species numbers: evolutionary accomplishments such as having a head, limbs, and complex organ systems for circulation and digestion don't seem to be primary accessories in the evolutionary "dress for success."
- SD
Oh, good. A key indicator for evolutionary success is to be a parasite.
Ed: I hope this is not an intro to anything political
Nah, I'm just curious about the science.
"We tested all these unique traits individually," Wiens explained, "for example, having a head, having eyes, where the species in a phylum tend to live, whether they reproduce sexually or asexually, whether they undergo metamorphosis or not; and from that we picked six traits that each had a strong effect on their own. We then fed those six traits into a multiple regression model. And then we asked, 'what combination of traits explains the most variation without including any unnecessary variables?' -- and from that we could reduce it down to three key variables."
- SD
There's the case for how they got down to the variables and maybe you'll have to take the validity of statistical analysis on faith but they know the language and result is novel.
The paper includes further analysis regarding the consequences of human behavior regarding animal extinction and you're invited to continue with the article on the link.
Make what you will of their conclusions about parasitism and we will skip any editorials / sci fi extensions of that but do have a ball on your own with it.
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