Thursday, July 18, 2013

Human Evolution - We are a walking ecosystem

We are quite similar to the African apes anatomically and genetically, especially to the chimpanzees and bonobos. Humans have 46 chromosomes in their cells while all of the great apes have 48. In reality, this difference is not as great as it would initially seem because the human chromosome 2 is a fusion of ape chromosomes 12 and 13 with most of the same genes.
Research on learning the entire genome of common chimpanzees was completed in 2005. A comparison between this and the human genome (completed in 2001) shows that 96% of DNA base pair sequences of humans and chimpanzees are the same. Most of the 4% difference is in duplicated non-gene segments. If only gene segments are compared, there is a 98% similarity. The genes that differ mostly control speech, smelling, hearing, digesting proteins, and susceptibility to certain diseases. These dissimilarities are to be expected given that we have been on essentially separate evolutionary tracks for 6-7 million years. During that time, we have been subject to somewhat different natural selection pressures. These differences led to bipedalism for our ancestors along with a much larger brain and, ultimately, speech.
A comparison of DNA nucleotide sequences of living primate species show that humans are most closely related to the African apes. Next in descending order of genetic closeness to us come the Asian apes, Old World monkeys, New World monkeys, tarsiers, and finally the lemurs and lorises. This genetic comparison corresponds exactly with a comparison of homologous primate physical traits. It also fits nicely with what we know from the fossil record. The prosimians were the first to evolve. Next came the monkeys, then the apes, and finally humans.
Dr. Dennis O'Neil Behavioral Sciences Department, Palomar College, San Marcos, California

Tyrannosaurus rex hunted for live prey

Tooth found in victim's tail shows carnivorous dinosaur did not just feed on carcasses.

Sunday, July 14, 2013

Slave Shackle, More Found On Blackbeard's Ship

This 18th-century iron shackle was recently recovered from the wreck of the Queen Anne's Revenge, which belonged to the infamous Caribbean pirate Blackbeard.
 Archaeologists with the North Carolina Department of Cultural Resources discovered the ship, which sank in 1718

 Such shackles were used to imprison people, such as slaves en route to the New World, prisoners being held for ransom, or unruly sailors being punished for misdeeds. The shackle was wrapped in rope to prevent chaffing on the wrists and ankles of the imprisoned person.

Pictures: Slave Shackle, More Found On Blackbeard's Ship

 The people are the slaves of Life, and it is slavery which fills their days with misery and distress, and floods their night with tears and anguish…I have followed man from Babylon to Cairo, and from Ain Dour to Baghdad, and observed the marks of his chains on the sand. I heard the sad echoes of the fickle ages…I saw the apprentice slaving for the artisan, and the artisan slaving for the employer, and the employer slaving for the soldier, and the soldier slaving for the governor, and the governor slaving for the king, and the king slaving for the priest, and the priest slaving for the idol. And the idol is naught but earth fashioned by Satan and erected upon a knoll of skulls.

I found the infant nursing the milk of slavery from his mother’s bosom, and the children learning submission with the alphabet.

Patriotism – She possesses various names, but one reality.  She has many appearances, but is made of one element.  In truth, she is an everlasting ailment bequeathed by each generation unto its successor.

 I found the blind slavery, which ties the people’s present with their parents past, and urges them to yield to their traditions and customs, placing ancient spirits in the new bodies. I found the mute slavery, which binds the life of a man to a wife whom he abhors, and places the woman’s body in the bed of a hated husband, deadening both lives spiritually.

I found the deaf slavery, which stifles the soul and the heart, rendering man but an empty echo of a voice, and pitiful shadow of a body. I found the lame slavery, which places man’s neck under the domination of the tyrant and submits strong bodies and weak minds to the sons of Greed for use as instruments to their power.
 I found the twisted slavery, which causes the tongues of the weak to move with fear, and speak outside of their feelings, and they feign to be meditating their plight, but they become as empty sacks, which even a child can fold or hang. I found the perpetual slavery, which crowns the sons of monarchs as kings, and offers no regard to merit.

When I grew tired of following the dissolute ages, and wearied of beholding processions of stoned people, I walked lonely in the Valley of the Shadow of Life, where the past attempts to conceal itself in guilt, and the soul of the future folds and rests itself too long.  There, at the edge of Blood and Tears River, which crawled like a poisonous viper and twisted like a criminals dream, I listened to the frightened whisper of the ghosts of slaves, and gazed at nothingness.

When midnight came and the spirits emerged from hidden places, I saw a cadaverous, dying spectre fall to her knees, gazing at the moon.  I approached her, asking “what is your name?”

“My name is Liberty”, replied this ghastly shadow of a corpse.

And I inquired, “Where are your children?”

And Liberty, tearful and weak, gasped, "One died crucified, another died mad, and the third one is not yet born.”

She limped away and spoke further, but the mist in my eyes and cries of my heart prevented sight or hearing.

Selection from The Treasured Writings of Kahlil Gibran
Kahlil Gibran (1883 -1931)

Tuesday, July 2, 2013

The Science of Love - Dr. Helen Fisher

Love means a lot of different things to a lot of different people. I study the brain and I think we’ve evolved three distinctly different brain systems, each one of them various people would call love. The three brain systems are the sex drive, the craving for sexual gratification linked with the testosterone system in both men and women. The second is romantic love, obsessive love, being in love, infatuation, whatever you want to call it, linked with the dopamine system in the brain. And the third brain system is attachment, that sense of calm and security that you can feel with a long-term partner. Other scientists have linked that with the oxytocin in the vasopressin system.
We found some things in all three types of people. We found activity in a tiny little factory near the base of the brain called the ventral tegmental area and we found the activity in some cells that actually make dopamine, a natural stimulant, and send that dopamine to many brain regions. And dopamine is associated with feelings of obsession and craving, euphoria, focus, energy and motivation, in this case the motivation to win life’s greatest prize which is a mating partner.
We did find some differences. Among those people who were in love long term; they no longer showed activity in the brain region linked with anxiety. You know when you’ve just fallen in love you are anxious, you get home and you lie in bed and you say what did I say that for, what did he mean by that, am I too fat, I shouldn’t have done this, I could do this—you’re anxious. And among those who are in love long term we no longer found activity in brain regions linked with anxiety. Instead we found activity in brain regions with calm and pain suppression. You still feel deep attachment to the person but that early stage insecurity, anxiety and tension is now replaced with calm.
Among people who had been rejected in love we found a great deal of activity in the brain region linked with the profound addictions. Romantic love is an addiction, it’s a perfectly wonderful addiction when it’s going well and a perfectly horrible addiction when it’s going poorly. And among those people who had just been rejected in love we found activity in the brain region linked with intense romantic love—you know if you’ve just been dumped you dislike the person even more and the reason being is because your amping up that dopamine system.
We also found activity in the brain region linked with deep sense of attachment among people who had just been rejected in love and last, but by no means least, we found activity in brain regions linked with pain and the anxiety that goes with physical pain. So when you have been rejected in love you’re craving the person, you’re madly in love with the person, you’re feeling deep attachment to the person and indeed you’re in physical and emotional pain. And in fact I recently read an article which actually showed that taking a Tylenol or an aspirin is actually good for the psychological and physical pain of romantic rejection. And sure enough that helps to understand my own data, which is that there’s physical pain when you’ve been rejected in love.
Dr Helen Fisher is a biological anthropologist and research professor at Rutgers University.