Tag Archives: Natural Selection

What’s in the air?

i-fc0baa42c324cefa8495fdb0044234b2-dice.jpgGood question … what IS in the air?The simple answer is that the air … the Earth’s atmosphere … is about 78% nitrogen, 21% oxygen, with a tiny amount of some other gases including water vapor. Then, there’s dirt. I want to talk a little about the oxygen, one of the other gases (carbon dioxide to be exact), the water vapor, and the dirt. Continue reading What’s in the air?

The Boneyard XIII

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Grrrrrrrrrrrrr….

Welcome to the Lucky 13th Edition of The Boneyard … the Web Carnival about Bones and Stuff.

“The Boneyard is a blog carnival covering all things paleo, from dinosaurs to pollen to hominids and everywhere in between. It’s held every two weeks (the 1st and 3rd Saturday of the month), traveling around to a different blog for each installment, connecting some of the best blogging on ancient life.”

The previous edition of The Boneyard is here, at Dragon’s Tales. The next edition of The Boneyard will be Here at Archaeozoology. If you would like to submit an entry to the next edition, you may do so here. As always, thanks to Brian for originating and managing this carnival.

Continue reading The Boneyard XIII

Genetics of Behavior: Fire Ants

ResearchBlogging.orgA common presumption is that behavior is part of phenotype, and since phenotype arises from genotype (plus/minus Reaction Norm), that there can be a study of “behavioral genetics.” This is certainly an overstatement (or oversimplification) for organisms with extensive and/or complex neural systems, such as humans and mice. Neural systems probably evolved (not initially, but eventually) to disassociate behavior with the kind of pre-determined micro-management of behavior that a simple gene-behavior link requires. However, in organisms with neural systems the size of the period at the end of this sentence, we often do see cases of allelic variations causing behavioral variation in the whole organism. The study discussed here is an example of this. Continue reading Genetics of Behavior: Fire Ants

The Language of Evolution: Do we want to use the d-word?

PZ Myers notes that Ken Miller is making a case for the term design in evolutionary biology. Miller simply claims that “design” comes from the usual, expected evolutionary processes (Natural Selection, etc.). PZ is not buying this bill of goods, and neither am I. One way to address this question might be to ask: “What would Darwin do?”

Continue reading The Language of Evolution: Do we want to use the d-word?

Proof that Noah’s Ark was Real

One of the most compelling argument that the story of Noah’s Ark is made up is the implausibility of having animals like tigers and lions together with animals like lambs and deer on the same boat for very long. The big carnivores would eventually eat the little cute furry things. The bunnies would be the first to go. But new evidence, shown on the Miracle Pet Show disproves this objection. Continue reading Proof that Noah’s Ark was Real

The Three Necessary and Sufficient Conditions of Natural Selection

Natural Selection is the key creative force in evolution. Natural selection, together with specific histories of populations (species) and adaptations, is responsible for the design of organisms. Most people have some idea of what Natural Selection is. However, it is easy to make conceptual errors when thinking about this important force of nature. One way to improve how we think about a concept like this is to carefully exam its formal definition. Continue reading The Three Necessary and Sufficient Conditions of Natural Selection

The Modes of Natural Selection

There many ways of dividing up and categorizing Natural Selection. For example, there are the Natural Selection, Sexual Selection and Artificial Selection, and then there is the Modes of Selection (Stabilizing, Directional, and Disruptive) trichotomy.We sense that these are good because they are “threes” and “three” is a magic number. Here, I’m focusing on the Mode Trichotomy, and asking that we consider that there are not three, but four modes of Natural Selection. This will cause tremors throughout the Evolutionary Theory community because Four is not a magic number, but so be it. Continue reading The Modes of Natural Selection

Happy Birthday Alfred Russel Wallace

i-fc88700fc2c140b083836019317d5295-wallace.jpgWe are reminded, via Mousie Cat at Evolving in Kansas, that Yesterday (I’m so embarrassed I missed this) was Alfred Russel Wallace’s birthday!Wallace was born in 1823.

We should now clearly recognise the fact, that the wealth and knowledge and culture of the few do not constitute civilization, and do not of themselves advance us towards the “perfect social state.” Our vast manufacturing system, our gigantic commerce, our crowded towns and cities, support and continually renew a mass of human misery and crime absolutely greater than has ever existed before. They create and maintain in life-long labour an ever-increasing army, whose lot is the more hard to bear, by contrast with the pleasures, the comforts, and the luxury which they see everywhere around them, but which they can never hope to enjoy; and who, in this respect, are worse off than the savage in the midst of his tribe.- A.R. Wallace in The Malay Archipelago, 1869.

The conclusion from these three independent proofs, which enforce each other in the multiple ratio of their respective weights, is therefore irresistible–that animal life, especially in its higher forms, cannot exist on the planet.Mars, therefore, is not only uninhabited by intelligent beings such as Mr. Lowell postulates, but is absolutely UNINHABITABLE.- A.R. Wallace in Is Mars Habitable? 1908

Life history trade-offs and human pygmies

Blogging on Peer-Reviewed Research

Every few years a paper comes out “explaining” short stature in one or more Pygmy groups. Most of the time the new work ads new information and new ideas but fails to be convincing. This is the case with the recent PNAS paper by Migliano et al.

From the abstract:

Continue reading Life history trade-offs and human pygmies