Field of Science

Carnival of Evolution 16 - the [find modest synonym for outstanding] edition



I am pleased beyond measure to welcome you to this 16th edition of the traveling Carnival of Evolution. Very pleased! Pleased beyond... measure.

So welcome. We all love statistics like [find appropriate idiom], so let's start with some of that.

This edition of the carnival consists of 36 posts (far too few) about evolution on ≈26 blogs (far too few), with a total of 50,228 words, for an average of 1,395.2 words per post. Standard deviation is 1,307.6. Count of words for each post is listed in brackets after each title, where I also note if the post is about a peer-reviewed paper (PR). Shortest post is 314 words, while the longest is 5,584 (counting Carl Zimmer's post and NYT article as one). Both praiseworthy achievements.

In a pitiful attempt at bringing some order to chaos, the posts have been forced into categories that many of them are quite uncomfortable with. I suspect I shall concomitantly receive much hate-mail, and will of course bend over backwards to please everyone by making any changes strongly suggested. I am serious.

To see the previous editions, please visit Carnival of Evolution, the blog, where you can also find the form to submit to next month's edition.

One of the posts this time is about a fine paper about experimental evolution, which I was intending to blog about myself. However, since it is also my desire to eventually publish papers in scientific journals myself, I never got further than writing this footy list of explanations of evolutionary terms particularly important for that paper. I'll link right here to the first who can guess which paper/post I'm talking about.

GLOSSARY OF EVOLUTION
Organism: A uni- or multi-cellular automaton with the ability to reproduce.
Fitness: A measure of the organism's ability to reproduce.
Genotype: The genetic make-up of the organism; the particular DNA.
Mutation: Any change in the organism's genotype (recombination, insertions, deletions, SNPs, inversions, duplications, translocations, etc.).
Beneficial mutation: Having an advantageous effect on fitness.
Deleterious mutation: Having a detrimental effect on fitness.
Neutral mutation: Effectively no change in fitness.
Population: A competing group of organisms.
Trait: A characteristic of an organism encoded by part of the genotype.
Selection: The increase of genotypes or traits in a population due to their fitness advantage.
Drift: A random fluctuation of genotypes or traits in a population.
Fixation: The event of a mutation becoming universal or very common within a population.
Substitution: A mutation that has gone to fixation.
Adaptation: The process by which the population increases its fit to the environment.


Lastly, before we begin, I must surprise everyone by revealing that this year Charles Darwin would have turned 200, and The Origin was first published 150 years ago. Both of which makes this carnival very special. Next year is going to be a real bummer.

Human Evolution

AK's Rambling Thoughts
Diagonal Postures & The Descent from Human to Ape (3,213, PR)
Guest blogger and author of The Upright Ape: A New Origin of the Species (2007) goes into details with a paper that argues that humans did not evolve from a knuckle walking ancestor.

A Primate of Modern Aspect
What microcephalics can tell us about human evolution (1,004, PR)
This post, to my surprise, is not about hobbits, but about the fact that humans with smaller brains than some chimpanzees can still do things chimpanzees can't (use tools and make fire, and restrict themselves to one lover).

Evolving Thoughts
Rudiments and vestiges (983, PR)
Does phylogenetic analysis support the claim that the human appendix has a function, or is it rather evidence that humans are primates?

Mailund on the Internet
Doubts about complex speciation between humans and chimpanzees (932, PR)
A paper argues that hybridization between humans and chimpanzees is not necessary to explain the lower divergence between their X chromosomes, compared to that between humans and gorillas.

Greg Laden's Blog
Is the latest claim regarding "chimp-human" inbreeding a bunch of hooey? (469, PR)
Another take on the paper about complex speciation between humans and chimpanzees.

Paleontology

A DC Birding Blog
A Man-eating Bird? (390, PR)
Did Haast's Eagle eat humans? At least it could have.
Figure: Comparison of the huge claws of H. moorei with those of its close relative the Hieraaetus morphnoides, the “little” eagle. The massive claws of H. moorei could pierce and crush bone up to 6 mm thick under 50 mm of skin and flesh.

Fresno, Evolving
A punk-size T-rex and an Eagle that ate children?! (1,752, PR)
Evolutionary pressures can cause body size to become smaller as well as larger. Not all Tyrannosaurs were huge (though nine-footers would still be scary), and Haast's Eagle wasn't as puny as the extant ones.



Natural Selection

NeuroDojo
Fence lizards versus fire ants: Evolutionary fail? (559, PR)
Lizards fail to adapt to venomous ants after seventy years. Perhaps a case of too little variation present for natural selection to act on?

Ionian Enchantment
Chameleons DO change their color to blend in with their environment (658, PR)
Does color change in chameleons serve only as social signaling, or also as camouflage? Which function was first selected for?

Mauka to Makai
Sperm Wars (552, PR)
Ironically, the selection pressure for females to get their eggs fertilized has resulted in the female reproductive tract making it difficult for sperm to get through.

Epiphenom
Why do atheists have fewer kids? (604)
Do the religious have more children than atheists because of honest signaling?

Pleiotropy
Adaptive depression? (736)
Two scientists argue that depression is an adaptation for thinking harder about our problems. Perhaps this is an example of applying positive selection where it doesn't belong?

Mailund on the Internet
A Method for the Simultaneous Estimation of Selection Intensities in Overlapping Genes (868)
A new method to estimate selection finds no evidence of positive selection in two influenza A genes, contrary to what is inferred in elsewhere.

AK's Rambling Thoughts
Homeotic Mutationism (5,584, PR)
Mutations in homeotic genes (e.g. Hox genes) can cause large developmental changes. Here we learn about the definition, causes, and possible consequences of homeotic mutations, with a nod to the otherwise universally predominantly dismissed “hopeful monsters.”

The Primate Diaries
Laboratory Evidence for the Breakdown of the Selfish Gene (1,674)
In The Selfish Gene (1976) Richard Dawkins championed selection on individuals, and group selection hasn't been regarded with much sympathy since. This is slowly changing, as experiments show that selection can work on groups.

Deep Thoughts and Silliness
Kin are a Group (1,480)
A reply to the post at The Primate Diaries: Selfish gene theory need not be expanded, because it already encompasses group selection via kin selection.

[Note: Both bloggers have promised me to continue the debate about group selection, and I will be adding links here when they get around to it.]

Molecular Evolution

The Chromosome Chronicles
Sexual Reproduction for Same Sex Couples? (1,170)
Pluripotent stem-cells can be made into either male or female gametes (sperm or egg), so it might be possible to have children who are genetically descended from two males or two females. I can't wait for the conservative Christians to go bonkers over this one. Note: Two females can only have female offspring. Wrap your head around the consequences of that.

The Atavism
Where did you get that preposterous hypothesis (1,774, PR)
A paper in PNAS suggests that metamorphosing organisms are hybrids between two distinct lineages (e.g. butterflies descend from a mating between a flying insect and an onychophran). The hypothesis is crazy, so why did it get published in a prestigious journal, PNAS? Get the answer here.

The Loom
The Continuing Adventures of the Blind Locksmith: You Can’t Get There From Here (165+846, PR)
Epistasis makes evolution irreversible. Make sure you click through to the NYT article.

Greg Laden's Blog
Evolutionary enamel loss linked to molecular decay of enamel-specific gene (437, PR)
Mammals evolved from an ancestor with enamel (hardest substance in the vertebrate body) covering its teeth. Genetic analyzes verify that enamelless and toothless mammals still have the gene to make enamel, but that mutations have made it a pseudogene.

Adaptive Complexity
Physical Chemistry Makes Us Different (1,722)
Key to understanding evolution is understanding genetic variation. How does genotypic variation generate phenotypic variation? Can biochemistry and genetics solve this problem?

Ionian Enchantment
Silver fox domestication (844, PR)
In the famous experiment on domestication of Silver Foxes the animals were selected for tameness, but also evolved other developmental traits that we know from dogs: shorter snouts, droopy ears, white patches of hair, &c. The hypothesis is that pleiotropy links these traits, so that tameness and the physical traits go together. But were the foxes really only selected for tameness?

NeuroDojo
Mousy blondes: Ready for evolution textbooks? (810, PR)
A skeptical angle on a paper that got a lot of press coverage. “This research would fail as a textbook example right now, fine work though it is.”

The Tree of Life
The Tree of Life: Why endosymbionts rule ... (314, PR)
A GC-rich bacterial symbiont with an alternative genetic code.

Lab Rat
Living without a cell wall... (723, PR)
How is living and replicating without a cell wall possible, and what does it have to do with the origin of life?

Creationism

Neuroanthropology
Sympathy for Creationists (5,364)
Can we find some sympathy for creationists through understanding their beliefs?

Birds & Science
Feather mites and God? (1,042, PR)
Roger's paper is picked up by creationists who conclude that feather mites knowing which bird feather will fall off next is proof of God.

Weird Things
Harder, better, faster, stronger? (384, PR)
Humans are still evolving and this is presented as evidence against creationism. If humanity would be the pinnacle of creation, then why are we still evolving?

The Tree of Life
Dembski still trying to play scientist (1,044)
Dembski published a paper in a peer-reviewed journal. It has been mauled and masticated, just like we like it.

Perspective

Skeptic Wonder
The Myth of Evolutionary Ascent (4,531)
If you still think that evolution has a goal, then this is the post for you.

Cubik's Rube
So You Think You Are a Darwinian? (2,501)
“Also, nature has given some creatures gills, also by Darwinian processes. Doesn’t mean humans have a moral imperative to breathe underwater.” Precious!

Evolving Thoughts
Dreams of memes and replicator machines (1,409)
Should we replace the notion of replicators by reproducers?

Skeptic Wonder
The Tree concept is quite alive and well, thank you (551)
Revisit the “Darwin was wrong” mess of the New Scientist for another argument that the tree of life is still a good description.

Beetles In The Bush
A Silver Anniversary (1,453, PR)
Beetle taxonomy. 25 years ago a new species of beetle was discovered in Missouri.

Books

Adaptive Complexity
The Indiana Jones Method Of Science (990)
A favorable review of Sean B. Carroll's newest book, Remarkable Creatures: Epic Adventures in the Search for the Origin of Species.

Pleiotropy
NSCE reviews (696)
The NCSE reviews evolution books, and a review of the review of Donald Prothero's Evolution: What the Fossils Say and Why it Matters gets axed.

☆ ☆ ☆

We have reached my only friend, the end. I hope you have enjoyed reading this 16th edition of Carnival of Evolution as much as I have writing it. Hopefully it has inspired you to learn more, and perhaps even to contribute to next month's edition, which will be hosted at Adaptive Complexity. So long.

7 comments:

  1. Mailund's piece on selection intensities?

    ReplyDelete
  2. Mailund's piece on selection intensities?

    Nope.

    ReplyDelete
  3. The glossary!!1! That paper is not what inspired me to make the glossary.

    ReplyDelete
  4. Thanks for the link. I'm moving to Frankfurt, so I might be a bit slow continuing on the group selection stuff, but i have intentions to do something.

    ReplyDelete
  5. THIS IS HUGE!1!!

    Well put together though!

    ReplyDelete
  6. A great line-up. Thanks for including my blog.

    ReplyDelete

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