7 Major "Missing Links" Since Darwin

In this rather fantastic photo segment from last year, National Geographic discusses the 7 Major “Missing Links” since Darwin. We’ve all heard the term “Missing Link” thrown around by skeptics and religious zealots alike.

The basic principle is that the “transitional fossil,” i.e. the fossil that actually connects two points of the evolutionary path has yet to be discovered. The biggest example is that there is a “missing link” between humans and apes.

The problem with that particular skeptics’ argument is that there’s no missing space. No Seriously, there’s not. There is nothing major missing in our fossil history. Scientists can document human evolution back to the common ancestor we have with modern apes.

So shut up.

I’m sorry, that wasn’t very scientific of me. But seriously, the battle is lost. You’re wrong. Science is bipartisan, facts are facts. If you still choose to, say, NOT believe in evolution… well, you’re wrong. Okay, sorry /rant.

In fact, recent studies discovered that modern humans even mated with our Neanderthal relatives.

Regardless, National Geographic says “The discoveries of these and other ‘missing link’ species have helped dispel what Darwin called ‘the most obvious and gravest objection which can be urged against my theory’ of evolution--the former lack of transitional fossil species.”

Tiktaalik – The “Fishapod”

The Tiktaalik is seen as evidence of when our aquatic ancestors began to move ashore. The Tiktaalik forms a strong branch of evolutionary evidence with eh Acanthostega (the most primitive tetrapod thusfar known).

Archaeopteryx: The First Bird

Archaeopteryx, the earliest known flying bird, was discovered within just two years of the publication of On the Origin of Species. It was the first discovery to fulfill Darwin’s prediction that fossil evidence would link major species groups. The Archaeopteryx linked dinosaurs and birds. Social/Popular acceptance of this theory has only been obtained recently. Even I can remember learning about dinosaurs as terrible lizard predators in the early 90’s (more than a century after Archaeopteryx was discovered).

Amphistium: The Halfway Flatfish

If you’ve ever seen a picture of a modern, flounder or halibut, you’re going to agree that they look pretty strange. The eyes sit on the top of the head, which is actually the side of the juvenile fish’s body. These fish lay flat on the ocean floor (thus their common name). It was argued by skeptics that because there was known fossil record of eye-migration over generations, that it must have been the work of intelligent design. In 2008. when Amphistium was had eyes that weren’t quite on one side of its head, but also weren’t quite on opposite sides of its head, properly demonstrating the “migration” of eyes over generations.

Ambulocetus: The Walking Whale

Discovered in 1922, the 50-million-year-old skeleton suggests that the creature was about to walk on four legs both on land AND in the water. Explaining how marine mammals, which possess vestigial limbs came from the land and went back to the ocean was a major evolutionary hurdle for Darwin. Ambulocetus is called “the most complete, best studied, and clearest case of something with a whale’s head, the beginnings of an aquatic lifestyle with webbed hands and feet, but still fully quadrupedal.”

Hyracotherium/Eohippus: The Dawn Horse

While this animal is known today as Hyracotherium (“hyrax-like beast”) it was originally called Eohippus (“Dawn Horse”). When Darwin went public with the theory of evolution, there was no hard evidence to show the linking of prehistoric species to their modern-day counterparts. Until Hyracotherium. When it was discovered in the southern US in 1867 it kicked off a series of fossil discoveries depicting the evolution of horses over 55 million years.

Thrinaxodon: The Emerging Mammal

Identified from fossils in both South America and Antartica (in and of itself supporting Pangea’s existence) this proto-mammal emerged on reptile filled Earth about 245 million years ago. Thrinaxodon serves as a practical “perfect” intermediate between mammals and reptiles and it has played a key role in unveiling the evolution of mammals. It was a cat-sized burrower that had scales and laid eggs, but like mammals, it had whiskers, warm blood, and (scientists suspect) a fur coat.

Homo ergaster: The “Turkana Boy” Species

Homo ergaster was a small-brailed but tall human species with body proportions similar to modern humans. The 1.6-million-year-old fossil of a child found in 1984 is often called Turkana Boy. Since the discovery of Java Man, the original “missing link” in the 1890s, the human tree has been easily populated with rich fossil evidence linking modern humans to ancient apes. One scientist is quoted as saying that Turkana Boy “is a true intermediate between modern humans and other primates.”

(All photos in this post are from HERE)

"Blow Job" Bats

For how thoroughly enjoyable the experience is, oral sex is actually surprising rare in the animal kingdom. Apart from humans (who obviously do our fair share), our close relatives the primates are the only other members of the animal kingdom known to partake… until recently.

Researchers recently observed oral sex for the first time in a non-primate species. During sex, the female short-nosed fruit bat has been observed licking the genitals of their partner.

(Photo Credits: AAAS)

Libiao Zhang and his colleagues from the Guangdong Entomological Institute in China, have been studying the mating behavior of the short-nosed fruit bat (Cynopterus sphinx). In the lab, they paired males and females in cages that mimicked their natural environment and infrared cameras beamed video of the bats’ exploits back to Zhang and his team at the lab.

For the most part, the animals reacted exactly as they had expected them to. The males of the species built tents made out of Chinese fan-palm leaves in order to attract the females. Both males and females groomed each other during their courtship. Then came the skinemax aspect, after the male bat mounted the female from behind, she bent over and began licking his penis.

According to the original report on PlosONE, of the 20 observed mating bat pairs, 14 of the females performed fellatio on the males they were with. The male bats never “withdrew” from the females while being licked. Authors of the study found that the longer a female performed fellatio on the male, the longer copulation lasted. According to the AAAS article, “for each second of licking, the female bats gained 6 seconds of copulations).

Zhang and his team speculate that the oral sex may prolong intercourse by increasing lubrication and helping maintain the males’ erection. The fellating females mated for an average of 4 minutes, nearly twice as long as their non-fellating counterparts.

Frans de Waal, a primatologiost at Emory University who has worked extensively with bonobos (the primate to partake in fellatio most frequently) announces that “the finding of fellatio in bats is exciting news.” He believes that the reason oral sex is rarely mentioned is due to the societal shyness about the issue.

(After what happened to Professor Dr. Dylan Evans at the University College, Cork, Ireland, when he showed his co-worker this study, I’m inclined to think that Mr. de Waal may be right.)

(Photo Credit: Huffington Post)

Regardless of societal objections, Paul Vasey, a behavioral scientist from the University of Lethbridge thinks that this discovery provides a unique opportunity to test some theories about the evolutionary role of oral sex.

Although it’s possible that bats are just being sexually playful like their human and bonobo counterparts, the discovery still suggests that there may be a biological advantage to fellatio (this line PROBABLY won’t work on your girlfriend the next time she’s not in the mood… but hey, it’s worth a try).

FOOTNOTE: Below is a particularly amusing/disturbing section from the original report about the…(um)… dynamics between males and females during bat-sex. (Not the delicious, Bruce Wayne kind).

“Sometimes the female appeared to resist, or even escaped by accident, and then the male would follow her until copulation was completed. In two instances, the female evaded the male for about eight to 25 seconds and turned to bite the male, but later the male followed her until mating was completed. In four instances, the female appeared to resist the male's approaches, but did not evade successfully, and copulations were eventually completed.”

I find myself laughing at the thought of the next Law & Order spin-off… Bats: SVU.

Timeline of Evolution (to scale!)

I'll update for real either later tonight or tomorrow, but I saw this and thought you should too.

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Steve Rose has created a to-scale timeline of evolution of life on earth. It's pretty amazing to look at. Once you click on the link, scroll to the right. Each inch on the chart represents about 2 million years.


Click the button on the bottom right to see a "zoomed in" evolution from our first walking ancestors to modern humans.

On his website Rose says "One of the things that I am most amazed about is how long the dinosaurs endured on earth, and how briefly humans have lasted, so far." I completely agree with him.

US Science Literacy Issues Swept Under the Rug

For a country founded on the idea of religious freedom, it seems counter intuitive that Americans are some of the least likely in the world to believe that humans evolved from earlier species or that the universe began with a big bang.

Anyone who considers themselves a scientist would assume that these basic scientific principles should be considered matters of scientific literacy. The National Science Foundation (NSF) agreed too, publishing the findings of repeated surveys of scientific literacy in their biennial report on the state of global science… until this year.

In a last minute and highly controversial decision, the NSF board decided to omit these key issues from the 2010 edition of Science and Engineering Indicators’ chapter on public attitudes toward science and technology. The section describing the survey results was edited out of the massive report by the National Science Board (NSB). The board is receiving flak from the White House and the nation’s science educators for its decision.

The NSB argued that the survey was misleading and didn’t properly reflect what Americans know about science. Survey authors vehemently disagree, stating that excluding the topics “downplays the controversy.” Joshua Rosenau of the National Center for Science Education stated that “discussing American science literacy without mentioning evolution is an intellectual malpractice.”

NSB officials insist that their decision to drop the survey questions on evolution and the big bang from the 2010 report was based on concerns over the nonpartisan nature of the survey questions. According to John Bruer, a philosopher and the lead reviewer for the chapter, he recommended removing the text because the questions “seemed to be very blunt instruments, not designed to capture public understanding.” Astrophysicist Louis Lanzerotti called the questions “flawed indicators of scientific knowledge because the responses conflated knowledge and beliefs.”

White House officials, to whom the board officially submits the Indicators report, were extremely surprised by the NSB’s action. The White House Office of Science and Technology Policy (OSTP) have asked for and were given the board’s explanation for the removal of the text. The authors of the survey disagree with the decision, and those struggling to keep evolution education in the classroom say the subject’s omission could hurt their efforts.

Science obtained a copy of the deleted text, which they say does not differ substantially from what appeared in previous editions of Indicators. The two questions have been part of a NSF funded survey on scientific understand and attitudes toward science since 1983.

The deleted section notes that the percentage of Americans who answered “true” to the statement “Human beings, as we know them today, developed from earlier species of animals” is similar to the survey results of other years (45%). This percentage shows that the public belief for human evolution is much lower in the US than in Japan, Europe, China, or South Korea, where 78%, 70%, 69%, and 64% of the public answered “true,” respectively. A similar international separation exists in response to the statement “The universe began with a big explosion,” to which only 33% of Americans agreed.

Bruer stated that by removing these sections, indicators could be developed that “were not as value-charged as evolution.” When Bruer proposed the deletes from Indicators last summer, he also recommended that the board drop the sentence noting that “the only circumstance in which the US scores below other countries on science knowledge is when many Americans experience a conflict between accepted scientific knowledge and their religious beliefs,” which, ironically, was a qualifier the NSB added to the report at his request that the offending sections be removed from the 2008 Indicators.

To support his claim, Bruer notes that a 2004 study found that 72% of Americans answered correctly when the statement about human evolution was prefaced with the phrase “according to the theory of evolution.”

George Bishop, a political scientist at the University of Cincinnati who has studied American’s attitudes towards evolution, believes that the board’s argument has merit. He is quoted as saying “Because of biblical traditions in American culture, that question is a measure of belief, not knowledge,” whereas in Europe and other societies, “it may be more a measure of knowledge.”

Tom Smith of the National Opinion Research Center, which conducts the science knowledge survey for Indicators disagrees with the idea that the questions are flawed. In fact, he believes that prefacing the questions with qualifiers might lead to flawed results since “that could have the effect of tipping respondents off about the right answer.” Smith says that NSF has yet to ask him to make any changes to the survey, which is slated to be used in the 2012 Indicators. NSF hasn’t asked for any changes… not yet, at least. Lanzerotti, as well as the director of the NSF’s statistical office say that it is time to take a fresh look at the survey questions.

John Miller, a science literacy researcher at Michigan State University says that “Evolution and the big bang are not a matter of opinion.” He argues that, “if a person says that the earth really is at the center of the universe… how in the world would you call that person scientifically literate?”

Miller believes, as do many educators who believe that evolution should be taught in the classroom, that removing the entire section from the Indicators report was a clumsy attempt to hide a national embarrassment.

As a comparison he says, “Nobody likes our infant death rate, but it doesn't go away if you quit talking about it.”