Friday, November 30, 2012

Goodbye, Mr Chimps

Historical Mansion of Lin An Tai, Taipei ( Taiwan)



I am at the lab usually by 8.00 AM. There are several others who work in shifts to observe and to be observed  because we conduct high end experiments and   hence the need for a 24/7 vigil. Parking lot is visible through the window and Chimps can see me  getting out of my car. He knows that   I get in early so that  I can get a spot  close to this building.  If it were in his power, he would  have ensured that this spot is reserved for me permanently. He is my best friend for the past several years, he has been here longer than me and knows  more than me about the lab and the people.  He grunts when I make mistakes, grins when my experiments are successful.  Usually as soon a  he hears my footsteps in the corridor, he gets up and, swings hanging onto the iron door frame. What a grip, it never slips, at least so far. I admonish him for such acrobatics “ You are getting old, be careful” , but he gives me a huge grin  and reaches for  the breakfast packet.  We split the breakfast – I always carry enough for two-  but not the banana, that is  for him only.

But today he seems  different,  gloomy   and withdrawn. Idiosyncrasies of old age?  Of late he doesn't like me spending too much time with others, did I stop in the corridor too long to exchange a few words with  M.?  You know he notices every single detail. I ask my colleague who was in the night shift and now busy packing up to leave, "What happened? He isn’t  feeling well, looks like .  Or you chided him for something  silly ?" 
“Oh you don’t know?  The authorities are planning to retire him”
“Retire? What  would he do ? At this age? And he has nowhere to go either” I am aghast. "But how did he come to know about it ,I mean did someone tell him specifically ?"
“Oh Come on, He has been here for the past 30 years and he is intelligent enough to understand the goings on. Did we not panic last year, when the talks on downsizing  where in the air ,without being told point blank?”
“Well, but he is a bit different, isn't he? But what would he do ? How will he survive? We can just turn him out “
“He is entitled to  receive full retirement benefits , including medical, I believe.  Better than what most  us can expect.  You know his entire family has  dedicated their lives from day one,  for scientific research.  Elder siblings Rita and Theresa were adopted by the NASA, a few others  were with the  health programs on infectious diseases, HIV/AIDS, cognitive and behavioral sciences …….....  Only the AIDS research didn’t lead anywhere, because they didn’t respond at all.    All of them- they are all much  older than Chimps - have now been retired and  you know what and are being rehabilitated in a resort. “
“You are kidding,  a resort? “
“No! this is not a joke. Chimps  too will be taken there. I hear it is a fantastic place with all modern  fittings, almost like a spa.  Chimps can finally be reunited with his family there. But alas, they may not recognize one  other."
"What do you mean, they won’t recognize?”
“Ha! You are really ignorant.  Chimps,  was  separated from  his biological mother the moment he was born,  just like Rita and Theresa and dozens of  others before them. They were all  bred for  very specific causes by different adoption  agencies.  So  there has been no family bonding whatsoever”.
 “Oh ,then  indeed poor darling will be miserable at the resort.”
“ You know, but that will be best for him, to be with his kith and kin at least   during  the sunset years, they are all very  intelligent, they  will get used to one another . That is the best  we can do for them, after all they dedicated their body and soul for scientific research. I don't mind a bit that we need to foot their retirement and medical benefits bill  ”
“Perhaps you are right, but  we must  visit him every week, how about every Saturday?  By the way what is name of this resort ? “
“ Chimp Haven, the National Chimpanzee Sanctuary, just 22 miles off Shreveport, in Louisiana. Not very far from here. It will be a nice picnic for the whole  family". 


Deeply moved by  a  report that  the National Institute of Health (USA)  is attempting  to rehabilitate  about a 100 chimpanzees, who are no longer of research value , since invasive research on Chimpanzees has become irrelevant. 

 “ NIH faces Chimp housing quandary “:Nature 491, 2012, page 18. 





Monday, November 5, 2012

Treading the middle path


Controversies are part of public life.  Allegations and assertions fly in from multiple sides. Media   committed to   Breaking News every second,  is no help either. Common man is left too astounded at the revelations and too confused  to choose between true and false.   One knows truth is somewhere in between or everywhere, but  nebulous and evasive.

One would have thought  things are very different in the scientific world. After all, science is the pursuit of truth and scientists are driven by hard data alone, not mere speculations. So there should  be just black and white with sharp boundary and  no intervening grey area. If only this were true! State of things are no different in the scientific world either. Only difference is it rarely spills out  into daily newspapers or news channels.  For example the controversy about the genetically modified crops.(1-4) While one group is ready to wager  everything to advocate that  GM crops are man’s best answer to the impending global food crisis, their opponents would leave no stone unturned to prove the opposite. The huge chasm between this divide is filled by  the “maybe/may not be” population  who would keep on  demanding more proof to decide one way or the other.

Another debate which rages on endlessly is the climate change. Well, everybody agrees that  global climate is  changing, but not on the causes,  consequences nor on the urgency to confront the issue.  Of course there is a tendency to link  the occurrence of every natural disaster to climate change has resulted in the trivialization of the issue.   Kerry Emmanuel of MIT has done a detailed study  on the occurrence of hurricanes in the US  and remarks  that  “anthropogenic climate change may have a substantial influence on tropical cyclone activity around the world ” (5).  No conclusive reports have appeared as yet on the genesis of Hurricane Sandy that lashed the US east coast last week.  

These are only minor aberrations. Scientists have always taken decisions, one way or the other. Or else man wouldn't have stepped on the moon, nor  polio vaccine  made.

Tailpiece:  
L’Aquilla (Italy) is  an earthquake prone city, the residents are  aware of that. During March-April 2009, seismologists detected spikes in the activity of Earth’s underbelly, but top scientists of the   NCFPMR (National Commission for the Forecast and Prevention of Major Risks, Italy) reassured the public not to worry,  nothing out of ordinary would happen.  But alas on 6th April 2009,   at about 3.00 AM the town experienced one of the worst earthquakes ever in the last 30 years.  Seven members of the Commission now stand convicted of manslaughter though not willful.  Their crime, not that they misread the signals , but that they mislead the residents into a false sense of “ all is well”, one of them  even suggesting that they relax with a glass of wine.
.
Sunset  from the shores of  Tungabhadra


References:
1.    Rat study sparks GM furore: Butler, Nature 27th September,2012 489,page484
2.    Hyped GM maize study faces scrutiny: Butler  Nature 11th October,2012, 490, 158
3.    Genetically modified plants and human health, Royal Society of Medicine 2008 vol. 101(6) .  290-298, Key et al
4.    Global Warming Effects on US Hurricane Damage: Kerry Emmanuel ftp://texmex.mit.edu/pub/emanuel/PAPERS/wcas_2011.pdf

Monday, October 1, 2012

TWAS 2012@ Tianjin


Science took me to Tianjin, a city, southeast of Beijing  in Mainland China during the  second half of September.
The  occasion was the 23rd General Meeting of the TWAS.  The acronym, TWAS, originally stood for the  Third World Academy of Sciences, with headquarters in Trieste Italy.  Formed in 1983, this started of as an excellent platform  for the   practising scientists and science & technology policy makers of the developing world to meet annually. Perhaps, members felt, the qualifier Third World had an archaic ring to it, so   in 2004, the name was changed to  Academy of Sciences of the Developing World,  though the acronym didn’t match.  But now in   a move to expand the boundaries  ( or rather remove it altogether) TWAS takes on a new avatar,   The World Academy of Sciences, and well  the acronym suits and hence  stays.). Anyway there are several   associate fellows   from the developed world. 

This year’s theme was  science, technology and innovation for economic growth. Chinese President Hu Jintao gave the keynote address. He mentioned that  China drew a  15 year roadmap in 2004, identifying activities and projects that would propel China to the frontiers in that time frame. He  promised 1.5 million US$ to the Academy  to boost  scientific cooperation and collaboration among the member countries. The Ministerial session that followed  had either the S&T minister himself or a top representative from S & T Ministry of   several of  the developing countries  addressing the audience. Mr Vylar Ravi, Minister for Science and Technology, India  also spoke. Particularly heartening was to listen to  efforts of Rwanda, Nigeria and Zimbabwe to alleviate poverty and improve quality of life  through innovations in S&T.  

Scientific sessions were  quite exciting and informative.  TB or not TB by Prof Richard N. Zare of  the Dept. of Chemistry, Stanford University covered his attempts to diagnose one of  most infectious diseases as early as possible.  Interested in the Life and Times of Dinosaurs? Anusuya Chinsamy-Turan of the Department of Zoology, University of Cape Town South Africa, analyses the microstructure of fossil bones to unravel the mysterious world of dinosaurs.
Tailpiece
What did a Bengali and a Keralite do when  they got some  free time in Tianjin?
While the rest went for shopping/site seeing, they visited the Zhou Enlai Memorial Museum. Here are some rare photographs from the museum 




Zhou Enlai & wife Den
May 4th Movement : A painting






Zhou Enlai's Appointment letter signed by Mao
A Copy of Red China





Zhou's letter to Chiang Kaishek


















Sunday, September 2, 2012

Art and Science of Hunger


Knut Hamsun  wrote  Hunger in 1890(1).  This Norwegian novel, set in Kristiania( modern day Oslo) , recounts the wretchedness of an aspiring  writer caught in the clutches of hunger. His unsolicited  essays are more often than not rejected    by  the publishers, and even on the rare occasions when accepted the reward is just  enough to cover food for a couple of days.   Poverty forces him to pawn every possible material possession he owns.  Partly autobiographical, the tortuous feeling of  hunger,  what it can do to  the physical and mental state of a human being, is splashed across the pages in vivid shades. His mind is at once delirious and sober, indulging  in snobbish fantasies  while still being acutely aware of the stark reality around.  Traumatized by hunger he even takes to chewing bark.   Thirty years later Kafka sketched the  " Hunger Artist"(2)  For Kafka's protagonist abstaining from food is an art and  he does it willingly out of no compulsion whatsoever. Proud of his skill, he is ever ready to demonstrate it under the watchful eyes of the  public ,   seeks no reward and ultimately  fades into oblivion.

Experts say that  one’s daily energy need could be as low as 1600kcals or as high  as 6000 kcals depending upon how heavily one sweats it out. (3) Coupled activity of two key hormones, at the hypothalamus,  ghrelin at the opening ceremony and leptin  during the closing ceremony,   orchestrates our feeding pattern(4). In other words, ghrelin is the start signal and leptin is the stop signal.   It indeed isn’t surprising at all that intense research in the area of obesity  has been instrumental in unraveling the intricate biochemical and neural pathways of hunger. Friedman (5)   and his colleagues at the Rockefeller Institute were doing precisely the same in obese mice population,   when they confronted  leptin  It is astounding that the amount of  leptin generated is proportional to the fat stored in the adipose tissue. That means there is a dynamic inventory going on.

Mutations in the leptin gene or lesions in the hypothalamus regions where leptin is supposed to exert its influence could lead to hyperphagia, a state where the body is in perpetually hungry mode leading  to overeating and obesity. Ghrelin the hunger hormone too acts at the hypothalamus, specifically  on a set of neurons called Agrp neurons.  If the AGRP neurons are provoked into frenzied activity   then again  hyperphagia develops. However,  if somehow  AGRP neurons can be sedated, then  the result is aphagia, loss of appetite and abstention from food.  August 9th issue of Nature carries a research paper by   Sternson and his team at the Janelia Farm Research Campus, Howard Hughes Medical Institute, Virginia, (USA), which tries to map the   neural circuitry of hunger.(6)  Their findings,  team hopes would prove helpful in  overeating disorders.
At the  Museo Nacional Centro de Arte Reina Sofia, Madrid  

2Hunger  Artist  in Selected Short Stories of Franz Kafka, Srishti Publishers, New Delhi 
4.  The role of leptin and ghrelin in the regulation of food intake and body weight in humans: a review Klok  Jakobsdottir  Drent ,  Obes Rev. 2007 Jan;8(1):21-34.
5. JeffreyFriedman 
6.The Deconstruction of a neural circuit for hunger : Atasoy, Betley and Sternson, Nature vol. 488, 9th August, 2012, pages 172-177



Wednesday, August 8, 2012

Our Microbial Secrets


Microbiologists and those who intently study the origin and spread of infectious diseases are dismayed. millions of people, drawn from  widely different  geographical locations  gather together for sports events like the Olympics or  World Cup , or religious events like the Haj or Kumbh Mela   yet, no major outbreak of infectious diseases has been reported. The Hindu religious festival Kumbh Mela where over 70 million people reportedly gather  and  dip into the same ( albeit, flowing ) waters, is another such unique event. Though there are stringent  guidelines regarding vaccinations against varieties of infectious diseases, the health hazards can never be undermined. Hence there is a new interest on closely monitoring  such " Global  Mass Gatherings" and scientists put their heads together  recently  during a three day conference in Jeddah, Saudi Arabia, Oct 23—25, 2010 

Scientists are divided on their opinion.  The argument that sports events usually draw together hale and healthy youngsters with the best  built-in  immunity profiles, and hence the chances of infections are rare could indeed be valid. However,  that is not the demographic profile at religious gathering. So there is something hidden from view, which guards against. Kamran Khan a specialist in Infectious Diseases, at St. Michaels Hospital, Toronto, Canada, has been collecting data for quite some time on the Haj pilgrims. He admits, tha the Saudi Government  indeed went to great lengths to prevent any kind of human disaster by insisting on the necessary immunizations as part of the pilgrims travel plans, screening pilgrims  at the arrival points, quarantining and treating the sick at lightening speed.  He quotes figures for 2009,  at the peak of  H1N1 scare,  2.5 million pilgrims visited Mecca, and less than 100 were diagnosed with flu.  Could it be that we are too paranoid about microbes and infectious diseases?  ( I can’t help but drawing your attention to an earlier piece  “Befriending Allergens”, where we discussed the benefits of being  on "Hello, How are you?" terms with  other life forms and  chemicals)

So a new project has been initiated,  Human Microbiome Project.(HMP). This is along the lines of the   Human Genome Project ( HGP) initiated about two decades ago, to unravel the locational and functional  mysteries of the genes encoded along the length of the human DNA chain. That exercise is complete, and we have plucked all the low hanging fruits. However  lot more remains elusive and enigmatic and scientists are in pursuit. It is altogether another matter that the HGP also dealt a rather a severe blow to our vanity that less than 25000 genes are enough to define a human being, and that is as much as the mouse needs too. 

What does the HMP endeavor to achieve? Scientists are already aware that the human   body is  literally the universe for  trillions of microorganisms  that coexist within us and on us,  Extensive studies have been carried out on the microbial communities in the gut  and have necessitated  that we do acknowledge the service they render to us. The HMP, intends to go beyond the gut microbiota, and do the  microbial mapping of the entire human body. Known for the precise and systematic methods, scientists  are  being site specific: Ear, nose,  mouth, throat,  under arms, inside elbows………………

Initial results have shown that the the microbiota map is very different from individual to individual  and then  within each individual there are umpteen site specific variations, too. Are we gearing up for another blow? The HMP might reveal that " We are, but what our microbes make us to be.!"

Tailpiece
Robert Hook (1635-1703)( of course,  the Hook's Law fame)  gave us the first concise book on the minute bodies.  Armed with just  a microscope, he explored the realm of  micro dimensions.  The book was published in 1666 by Royal Society of London. And then in 1675, Antonie  Van Leeuwenhoek  (1632–1723) established that there are life forms, so small that they are not visible to the naked eye.  



References:

1. Reflection and reaction The Lancet Copnference on Mass Gathering Medicine ,
      Lancet Infectious Diseases pp 818-819,  vol.10, 2010, McConnel and Memish

2. Infectious disease surveillance and modelling across geographic frontiers and scientific   
    specialties  The Lancet Infectious Diseases,  pp 222-230, Vol. 12(3).2012     
    Dr Kamran Khan MD, and others

3. Tackling the Microbiome, (Editorial, L Hood), Science , 1209 vol.336, 2012

4.  Do Sports Events Give Microbes a Chance to Score?, Kupferdchmidt. Science 1224- 
    25, vol.336 2012

5.  Science, All articles in the  special section 1245– 73 , Vol  336, 2012.







Wednesday, June 20, 2012

The Inheritance of Violence






According to Bible,   the very first murder  was committed by the very first  naturally born human .  The first  born of Adam and Eve,  Cain,   contrives to murder Abel, his own  brother, in a fit of jealousy.  Ever since that  first murder,   violence  has  became a part of human  life.   Violence must have been the quintessential quality of  the primitive  man,  when he had to coexist with the wild animals in accordance with jungle laws. Living in unfriendly terrains meant his  very existence depended on  his muscle power.  From the hunter gatherer,  as he,  ever so slowly,  metamorphosed  into a farmer,   he  acquired or rather developed certain extraordinary skills.   First of all he learned the  economics of  survival ,  the trade off between productive   foraging  versus  self annihilation.  Alienating himself from the jungle, he  tamed and domesticated  wild animals and plants  for his own selfish needs. As a part of  community living he also learned to communicate more effectively  with his kith and kin. The clicks and clocks of the tongue gave way to well structured languages   One would naturally conclude that language would have  at least to  some extent,  mitigated  mindless violence by facilitating   arguments  debates, discussions, negotiations and compromises.  



In fact Sigmund  Freud would have us believe that  man had to willingly suppress  his animal instincts,  especially the aggressive trait,  in order to set up a civilized society(1).     Incidentally I have been (re)reading the La Bete Humaine  ( The Human Beast)  written  in 1889 by Emile Zola (2).  The story is  set against the backdrop of industrial revolution and introduction fo railways in France.   The protagonist in the novel, Jacques, an engine driver,   is besieged with a violent urge to kill, whenever he tries to get intimate with a  female. He himself  is exasperated and deeply traumatized by this strange trait within. He tries to reason with himself, but  to no avail. At one point he concludes that this is a  trait inherited from the primitive man and can’t be just wished away.  

That is when  the issue of Science dated 18th May 2012 (3)  arrived with a  special section on violence.   Violence is analyzed and interpreted from various angles.  There is no conclusive evidence that civilized man is less prone to violence than the primitive man. There are enough arguments for and against.  This particular  issue of Science  is worth reading  not just once, but many times over.  In a  very concise yet incisive  editorial,  Professor David Hamburg  emphasizes the need to contain violence, as we contain a contagious disease. Look for early symptoms  and  prevent the spread then and there.  There is no single,  simple  answer to how violence erupts.  But with a  better sense of the after effects of  mindless violence, we should be  able to  " manage " it ;   this is the least we can do as human race . 

Scholarly essays  spread over  80 pages  deal very seriously with  the genesis and  developmental sociology of  human conflicts and violence.    But then  came relief  in the form of examples from animal kingdom.(4) Though we inherited the trait from them,  they don’t always resort to a "fight to kill  policy" to resolve conflict.  There are many other ways of  shooing  and scaring the enemy away, so  why fight to kill and be killed or injure and be injured?   Take the case of  Australian ants,  Iridomyrmex  purpureus,    They have a battalion of able bodied members forming the  Border Security Force, forever   safeguarding their territorial boundaries.  The  honeypot ants occasionally  hold power displays or  friendly matches  just to profess their  strength,  " Stay away, See what we are capable of".   And then  the practice  among the  green wood hoopoe,  a bird native to South Africa. Living in groups,  they defend their territories and  scare away intruders and enemies  by simply  calling as loudly as possible. 

1. Das Unbehagen in der Kultur   ( Civilization and its Discontents) S. Freud
2. La Bete Humaine ( The Human Beast)  Emile Zola
3. Science  vo. 336, 18 May 2012   pages 818-884
4. Elizabeth Pennisi, Science  vo. 336, 18 May 2012 , pages 828& 838
Nature's flower show at IISc Campus 

Sunday, May 20, 2012

ICE ICE, BABY


 (View from Gulmarg: Photo taken on 13 May 2012 by PRC
It was not so long ago that we received a severe jolt  from the Intergovernmental Panel on Climatic Change (IPCC) that  the Himalayan glaciers  will be disappearing into thin year by roughly 2035.  This meant  serious  repercussions. Possibility of   rivers of Indian Peninsula and China, which originate from these glaciers, drying up, loomed large.  What an  unimaginable socio cultural, economic  and geopolitical  crises this would lead to ?  2035 is too close  a time frame  for comfort    and there  was frenzy all around.  I am sure there might have an unprecedented rush to visit the holy shrines and scenic places in the Himalayas before it was too late.    Fortunately for everybody , the preposterous hypothetical prediction was soon withdrawn,  with the  explanation that all parameters  that   govern the waxing and waning of glaciers  were not taken into account.   

Though almost akin to bank balance it is indeed it is very difficult to monitor the  credit and debit pattern in ( or of) glaciers.  Credit  accrual  is when snow fall and avalanche get deposited and  debit is through melting  and caving.   But  these don’t appear as neat line items on adjacent columns as in a bank passbook,  so that we can check out the balance easily.   (In a way it is as unpredictable as  foretelling the occurrence of  puddles  that  rains leave behind  along the length and breadth of  Bangalore roads. ).   Sure  there are so many unknown debits and credits, but then there  is so much of balance  as of now that we needn’t worry for the time being.  Still there are causes for concern.  Because  aren’t there  instances,  when family  wealth,  accumulated over generations, is often splashed away  by spendthrift  great grand children in a jiffy?

Hence it cannot be denied that global warming will  adversely affect the glaciers, however imperceptibly it might be.   Attempts  are being made by several scientific groups globally  to study this . Bolch et al (1) in the April 20th issue of Science ask the pertinent question: How can we  make periodic,  three dimensional (length, depth and area) inventory of the  glaciers?.  In their opinion, location observatories, coupled with   remote sensing  techniques  and accurate modeling  would be one step forward.  Just as  the high and mighty Himalayas, Antarctic ice sheets   too  are  sending faint yet  sure signals of melting.  Pritchard et al ( 2) draw our attention to the fact that  the  repercussions may be felt   in a time frame of decades,  as an  infintesimal yet definite  increase in sea level.

Warm climates have ushered in  other unexpected ecological changes, so Pauli et al (3)would like us to believe.  Over a seven year period the team  monitored the  biodiversity (floral) across major mountain ranges in Europe.  The results seem to justify their  hypothesis that global warming might  drive plant species up the  mountain slopes. It would indeed be interesting to conduct a similar study along the Himalayan slopes.  First in the series should be " Is the Valley of Flowers receding ?"  Would be exciting to be part of such a scientific expedition.  

Europe has been closely monitoring  Mother Earth , through its eyes in the sky the  ENVISAT.   Since  2002 this satellite has been  providing European Space Agency (ESA)  with the vital statistics of Earth through a variety of multiply enabled instruments.  ESA received signals from ENVISAT till 8th of April 2012.  Since then there has been no contacts.  The implications are that the satellite's main computer or the power up system  might have failed. This has crippled a lot of agencies who are dependent on data from ENVISAT (4) 
Tailpiece :
Read about an interesting experiment to protect the glaciers of Alps.  Those concerned decided to  insulate them by wrapping them in  blankets ! 

References :
1.The state and fate of Himalayan Glaciers : Bolch et al  Science 20th April 2012, Vol. 336, pages 310-314
2.. Antarctic ice-sheet loss driven by basam melting of ice shelves : Pritchard et al  Nature 26th April 2012, Vol. 484 pages 502-505
3. Recent plant diversity changes on Europe’s mountain summits: Pauli et al  Science 20 April 2012, Vol. 336, pages 353- 355.
4. Europe loses sight of Earth : Brumfiel, Nature 26th April 2012, Vol. 484, page 423

4. Europe loses sight of Earth : Brumfiel, Nature 26th April 2012, Vol. 484, page 423

Friday, April 20, 2012

Evolution : FACTS and FUN



Evolution is a  serious  game in progress, of course at an impercetably slow pace. For us mortals, with short  life spans,   nothing really changes.   Mother Nature,  with her assistant  Natural selection, has been   playing the same game of speciation and divergence for close to 4 billion years. 

            One of the best fossils to study  various aspects of evolution   is the  simple tooth. (1).    In fact many extinct animals have left  behind only their fossilized teeth for us to know and  weave tales about them; how big  they might have been and what they would have eaten.  There are indications that though  jaws and teeth evolved independently, somewhere along the  evolutionary time lines, their pathways merged with the result that several things were firmly established once and for all.  The location of the teeth  on the jaws,  their function and  enabling dental features.  The frontal incisors and canines  help in  grasping and tearing, premolars and molars are  predominantly grinders, though they can also cut.   Cusps, the conical projections    on the surface of the molars  are   the enabling features to aid grinding and cutting process.    From the single cuspid reptilian to multi cuspid mammalian, there  are large variations in the dental features between species, but  relatively less within a  given species.   

            Harjunma et al(2) were fascinated by the developmental biology of  molars in laboratory mice.  Mice teeth are limited to   incisors and molars. In laboratory bred  mutant and transgenic mice very often cusps  are totally absent.  Except aesthetics,  these flat teeth may not have much functional use. Poor mice, flat teeth would have  robbed them off the whole  enjoyment of eating.  But why flat teeth, what leads to such a strange situation?.  Scientists have identified at least 29 gene mutations which can affect teeth formation in multiple ways, absence of cusps included. Mutation (altered  message) is one thing and signalling, (sending the message across to  intended recipients) is another thing.  Signals are clues to  turn on or turn off  or slow down  specific biochemical processes.   Tinkering with three such signalling pathways simultaneously   the team could ultimately increase the number of cusps even beyond the normal.   Harjunma team suggest that  there could be  multiple genes  at work in imparting cusp pattern to molars.  Adjusting  three genes they could make the cusps reappear, but then, in all possibility,  something else might have  gotten  impaired ?  No wonder evolution is a slow process, it is so intricate, so many messages need to be so finely balanced.......
 A friend of mine, who is working in the area of drug research,  spoke to me recently about   the  long years of study needed to zero in on a drug molecule.  A very promising  drug molecule  may prove to be causing some other ailment as a side effect. For example it might cure cancer but might lead to blindness. That is not acceptable.  Biological signals are never dedicated " For your eyes only"  type. One single signal  might be meant for several recipients and each  recipient  might interpret it in a different way. Hence the need for fine coordination. And that takes enormous amount of time.  
“Tailpiece
Playing the same game for close to 4 billion years  is not  a joke. Boredom is sure to  creep in at times and  that  is when Mother resorts to a few naughty tricks and treats. Her lazy assistant Natural Selection lets the players fight it out for survival, to decide   who wins and who gets wiped out.  Evolutionary biologists of course would  interpret these  as are necessary and well orchestrated  examples of  adaptive evolution, or survival tactics.   But just imagine wouldn’t it  be more fun to accept these as simple acts of pranks?  Take for example.  the rampant  practice of mimicry(3,4)the   Australian insect which resembles a twig,  the harmless hoverfly  which imitates the looks of the  sting bee,    the  venomous Texas coral snake and its innocuous twin, the  Mexican milk snake. 
More about mimicry  later 


1.Evolution and development of teeth McCollum et al   J. Anatomy. 2001 199, pp. 153-159
2. On the difficulty of increasing dental complexity: Harjunmaa et al Nature 2012, March 15, 483, 324-326.
3. Comparative analysis of the evolution of imperfect mimicry  Penney, H D et al, Nature 2012 March 22,   483, 461-464
4. A taste for mimicry ; Ruxton et al  Nature 2005 , January 20 433 205-206

Thursday, March 15, 2012

Social Networking: From Paleolithic to Facebook Era ........


Hadza(1) is a fast disappearing aboriginal tribe in Eastern Africa; Tanzania to be precise.   Hunters and gatherers for several thousands of years,(naturally, women are the gatherers and men the hunters) they communicate through clicks(2). They live  usually in small  groups of about 25.  The groups are loosely knit; members could come and go as they please, no questions asked nor answers sought.  Personal freedom is at the zenith.   Married couple can opt out of matrimony by living separately  for a fortnight, or by  adopting  the dress code of the  unmarried.   To  our civilized myopic eyes their  social norms or traditions are just a blur or altogether nonexistent.   

In forager societies there is no concept of personal wealth.  They live for the present, no hoarding  or saving.  Hunting is not an individual, but a team  effort, so also consuming the  prey.  Gathering may be a n individual effort, but the amount gathered is  so much that it is   shared.    How does such a group come together? Or rather  what holds such a heterogeneous  group (of  young and old, men and women,  active and lazy) together?   There indeed has to be a high degree of give and take or in modern terminology  Cooperativity.  Do like minded members seek out  each other ?  Are conflicts always settled by those with divergent views moving out?     Apicella and team  (3) reasoned that this is a  ideal system to study the intricacies of human interactions   since  prehistoric times. Because the Hadza haven't changed their ways in the least bit except perhaps  discarding the animal skin loin cloth for the manmade fabric. 

The  research paper published in January issue of   Nature (3)  reports   the social   networking pattern among Hadza tribe. 205 adults (men and women)  spread over 17 groups  were studied.  The sample size may not appear statistically significant;  yet considering the dwindling population, there  indeed is no other option but to accept. The affinity between individuals within the group and  outside group  and their voluntary contributions  for  a common cause came under scrutiny.  The methods used might sound a bit trivial. For example person to person affinity was  measured in terms of  sharing /gifting honey sticks ( high prized item among Hadza) and  choosing a preferred  group mate from a set of photographs.  The team concluded that  cooperativity is the glue that holds a group together. This could spring from  genetic,(parents, siblings, cousins) affinal (marriage)  ties or simple friendship.  They found cooperators  tend to flock together,  and often influence the  non-cooperators to fall in line, or else, get left out.   There is always an undeniable  element of  emotional quotient  when humans are involved. Somehow that seems to be absent in this study.   
  
If cooperativity  is at the core of social networking during prehistoric times, is it relevant today too? What better social networking site than the Facebook, a  vast network of friends and friends’ friends.?  Lewis et al (2) mapped  more than 1500 jottings by college students over a 4 year period, from the time they first entered the college till  they graduated out.  In principle could as well  be  a ‘Developmental Sociology”  project.  Lewis and team are cautious in the anlysis and interpretation of their data.   They did observe  is a tendency to seek out those who have similar tastes in music and films  however no trend to influence others. 


(1) Hadza_people

(2) Click_consonant

(3)Social networks and cooperation in hunter-gatherers: Coren Apicella, Frank W. Marlowe,James H. Fowler and Nicholas A. Christakis,  Nature 2012 481,497-501

(4)Social selection and peer influence in an online social network :


  • Kevin Lewis
  • Marco Gonzalez
  • and Jason Kaufman,   
  • Proceedings of the National Academy of Sciences 2012 109 (1) 68-72;