Showing posts with label உயிரியல். Show all posts
Showing posts with label உயிரியல். Show all posts

Tuesday, 12 February 2019

An Index of Biology essays உயிரியல் கட்டுரைகள்

An index of my biology essays

Kamshilov's fascinating Graph of Life
Symbiogenesis - Lynn Margulis
Plant evolution and Diversity
Creatceous Flora fossils in Gunduperumbedu
Guns, Germs and Steel - a book review
Contributions to Theory of Natural Selection by Alfred Russel Wallace - a book review
A brief timeline of Vaccinations


வரப்புயர்த்திய வல்லவன் - நார்மன் போர்லாக்
நூல் அறிமுகம் - துப்பாக்கி, கிருமிகள், எஃகு (Guns Germs and Steel)
சொர்கத்தின் பறவைகள் - ஆல்பிரட் ரஸ்ஸல் வாலஸ்
தோற்று பின்வாங்கும் நோய்கள்
கப்பலோடிய ஆங்கிலேயர் - நூல் விமர்சனம்
கம்சிலோவின் உயிரின கணக்கு
சலைவன் வாழ்த்து – (கவிதை) திணைகமழும் உதகைவனம்
கிளிவாழை கவிதைகள்


Friday, 23 June 2017

சலைவன் வாழ்த்து – திணைகமழும் உதகைவனம்

குறிஞ்சிவன மலர்கடிகை
உதகை தாவர பூங்கா


சலைவனெனும் அயலவனின் செயல்திறமை சிகரமிதோ
தலைவனவன் ரசனையிலே வளர்ந்ததுமோர் நகர்வனமோ
பனிபடரும் வரைதொடரில் பழங்குறவர் பயன்பெரவும்
வனிதவெழில் வளர்த்தவனை வணங்குகிறேன் தமிழனென

கதிரவனின் கடுமையிலே மருதமுமே சுருண்டிவிட
இதமிதுவே எனவறிந்து கம்பெனிமார் களம்புகவே
உதகையிலே உதித்ததொரு தலைநகரம் வெயில்தணிய
யதுகையென துளிர்ந்ததுகாண் கலைமிளிரும் மலர்வனமும்

மலர்வழியே உவமைகளை உறுகவியோர் உணர்த்தினரே
பலரறியா புதுமலரால் உதகையிலே உழவுசெய்தெ
திணைகமழும் தமிழ்மொழியும் திளைக்கிறதோ புதுவரவால்
அணைத்ததுயார் இயற்கையன்றோ இலக்கணமே மறுமலர

அறம்பொருளும் அகத்திணையும் பழம்புலவர் பரவிவர
குறிஞ்சிவன மலர்கடிகை செடிமரங்கள் அறிவியலாம்
புவிபொலியும் புதுகலையை தமிழ்புரிந்த சலைவன்வழி
நவிலுகிறேன் திணைவளர பலவிரும்பி இவண்கோபு

 
சலைவன் நினைவகம், கன்னேரிமுக்கு

ஜான் சலைவன், நினைவகத்தில் ஓவியம்

முதன்முறை கடந்த மே மாதம் உதகமண்டலம் சென்றேன். கோவையில் ஒரு தொல்லியல் மாநாட்டில் பங்கேற்றபின், நண்பர் ஓவியர் விசுவனாதனுடன் இரண்டு நாள் கோத்தகிரி பயணம், அதில் ஒரு நாள் உதகை சென்றேன். இருளர், படகர், தோடர், கோத்தர், குரும்பர் எனும் ஐந்து மக்கள் வாழும் மலைகளுல் உதகமண்டலமும் ஒன்று. கோத்தர் வாழும் மலை (கிரி) கோத்தகிரி. ஜான் சலைவன் எனும் ஆங்கிலேய அதிகாரி 1819இல் கோத்தகிரி வந்து அதன் இயற்கை எழிலில் மயங்கினார். அதைவிட மதறாஸ் மாகாண கோடை வெயிலிலிருந்து தப்பித்து தஞ்சம் புக இதை விட சிறந்த இடம் ஏதுமில்லை என்று உணர்ந்தார்.

பின்னர் கோடைக்கால ராஜ் பவன் உதகையில் உருவாகி அதற்கு ஒரு தோட்டமும் அமைந்தது. அந்த தோட்டமே பின்பு ஒரு தாவர பூங்காவாக மாறியது. இன்றும் கண்காட்சிக்கும் ஆராய்ச்சிக்கும் சிறந்த தடமாக விளங்குகிறது.

இங்கிலாந்தின் தலைநகர் லண்டனில் உலகின் பிரதான ஆராய்ச்சி தாவர பூங்காவாக கியூ தோட்டம் திகழ்கிறது. விசித்திரம்! உதகை பூங்காவை வடிவமைத்தவ தாவர நிபுணரின் பெயரும் கியூ! பரிணாம வளர்ச்சி கொள்கைக்கு புகழ்பெற்ற சார்ல்ஸ் டார்வினின் நெருங்கிய நண்பர் ஜோசஃப் ஹுக்கர் அக்காலத்தில் லண்டன் கியூ தோட்டத்து ஆளுனர். ஹுக்கர் உலகின் மிகச்சிறந்த தாவர ஆய்வாளரில் ஒருவர். இமய மலையிலும் சில வருடங்கள் அவர் தாவர ஆய்வுகளை நடத்தினார். தென் அமெரிக்காவில் விளையும் ரப்பர் மரத்தை ஆசியாவுக்கு அறிமுகம் செய்து மிகப்பெரும் ரப்பர் தோட்டங்களுக்கு மற்ற வணிக செடிமரங்களுக்கும் வழி வகுத்த புகழுக்கு உரியவர்.
1848ல்  கியூ வடித்த முதல் தாவர தோட்டம்

இருளர், படகர், தோடர், கோத்தர், குரும்பர்

உதகமண்டலம் 1837,
சல்லைவன் நினைவகத்தில் ஓவியம்
உதகமண்டலம், மே மாதம் 2017
(
பங்குனி ஹேவிளம்ப வருடம்)

ஹுக்கர் வட இந்தியாவில் செய்ததற்கு, தமிழகத்தில் சலைவனின் முன்னோடி. சலைவனுக்கும் சென்னையில்  ஆண்டர்சன், புக்கானன், என்று சில தாவரவியல் முன்னோடிகள் கோலோச்சினர். சலைவன் சான்றோராய் மலைவாழ் மக்களின் நினைவில் நிற்கிறார். ஐரோப்பிய காய், கனி, மலர் வகைகளை உதகைக்கு அறிமுக படுத்தி, தோடர் கோத்தர் போன்றோரை சமகால சமூகத்தில் சேர்த்தவர். கோத்தகிரி அருகே உள்ள படகர் கிராமம் கன்னேரிமுக்கு. அங்கே அவர் முதலில் தங்கிய வீட்டை மாவட்ட ஆட்சியர் புனரமைத்து ஒரு நினைவகமும் சிலையும் நிறுவியுள்ளார். அந்த நினைவக இயக்குனர் திருமதி காயத்ரி பொருமையாக பல தகவல்களை அள்ளி தந்தார்.

தாவரவியலில் எனக்கு நுனிப்புல் மேயும் ஆர்வமுண்டு; ஆழமில்லை. தாவரஙக்ளின் வரலாறும் மலர்களின் வரலாறும் மிக சுவராசியமானவை. சமீப கால பரிணாம உயிரியல் ஆய்வுகளின் படி விலங்கினங்கள் தோன்றி பத்து கோடி ஆண்டுகள் பின்னரே தாவரங்கள் தோன்றின. அப்படியானால் அதற்கு முன் விலங்குகள் எதை தின்று வாழ்ந்தன? வேறு கட்டுரையில் எழுதுகிறேன்.

உதகை கோத்தகிரி போன்ற பழங்குடி மக்கள் சங்கம் முதல் நாயக்கர் காலம் வரை தமிழ் சமூகத்தின் விளிம்பிலேயே வாழ்ந்து வந்துள்ளனர். சங்க புலவர்கள் உவமைகளில் பலவித மலர்களும் மன்னி மணந்தன, மின்னி மிளிர்ந்தன. ஐந்திணைகளின் பெயர்களே மலர்களின் பெயர்கள்தாம். ஜெயமோகனின் உரையால் எனக்கு இதன் ஆழமும் அகலும் உறைத்தது.

ஆங்கிலேயர் ஆட்சி வரும் வரை பறைசாற்றி அலச தமிழில் அறிவியல் சார்ந்த நூல்களோ ஆய்வுகளோ இல்லையென நினைக்கிறேன். இருந்தால் தெரியபடுத்தவும். சலைவன் வழிவந்தோர் தமிழ் நிலத்திற்கு உதகை பூங்காவை போல பல புதிய ஆய்வு தளங்களை பரிசளித்துள்ளனர். அவற்றை தழுவிய நூல்கள் சிலவே. சலைவனுக்கோ தாவரவியலுக்கோ வாழ்த்து பாடல் உள்ளதா என்றறியேன். தோன்றியது எழுதினேன். உதகை பூங்காவை குறிஞ்சிவன மலர்கடிகை என்றும், தாவரவியலை புதுத்திணை என்றும் நான் புனைந்தது மிகையாகாது என்றே நினைக்கிறேன். வீரமாமுனிவர், சென்னைப்பட்டணத்து எல்லீசன் வழியில் அயலவன் சலைவனை தமிழனென மொழிந்துள்ளேன்.

கவிதைகள்

தொடர்புடைய கட்டுரைகள்
1. சங்க இலக்கியம் – ஜெயமோகன் உரை  (ஒலிப்பதிவு)
2. தமிழில் கலைச்சொற்கள் – ஜெயமோகன் கட்டுரை
3. டார்வினுக்கு ஹுக்கர் செய்த உதவி
4. கம்சிலோவின் உயிரின கணக்கு



Tuesday, 7 February 2017

1493 - The Columbian Exchange

Charles C Mann spoke about his book 1493, at the MS Swaminathan Research Foundation on 9 December, 2016. These are my notes from that lecture.
----

There was once a geological era, about 300 million years ago, when all the continents of the Earth were united into a single supercontinent, called Pangaea. Later this continent split up, forming the continents we have today, primarily separating into two large land masses – the Americas on one side and Eurasia and Africa on the other side, separated by the Atlantic ocean one way and the Pacific the other. These two oceans passed huge species barriers. When Columbus sailed from Spain to the Carribean, in 1492, he effectively recreated (or reunited) Pangaea – his ships and its successors bridged the Atlantic, thus providing for a massive biologcal exchange.  Animals, plants and germs from Eurasia traveled into Americas. Alfred Crosby coined term Columbian exchange to describe this.

No domesticated animals like cattle sheep goats chicken horses or their equivalents existed in the Americas, in 1492. This triggered a massive epidemiological imbalance – the native epidemic diseases of Europe were more numerous and more deadly than those of the Americas, and caused a massive genocide of Native Americans, i.e. Red Indians, who had no immunity to European diseases.

The Cold Snap in Europe from 1550s to 1750s, was followed by Dutch paintings of children skating on iced over rivers in April. These rivers have not iced up in the recent two centuries. The massive death of people in the Americas, meant they stopped cutting trees to burn them, so forests grew back and sucked out so much Carbon dioxide from the atmosphere, that they caused the Cold Snap, a mini Ice Age. (This is usually not mentioned in newspaper reports about Global Warming).

Europe was poor while China India and Ottomans were rich, until Silver was discovered in South America by Spaniards, mostly in Peru. In fact they discovered a hills of silver.This trebled the world supply of silver. Europe could now buy Asian goods with their silver.

Wheat went from Europe to the Americas and potatoes and chilis from the Americas to Europe. Mann shows photographs of wheat farms, then says, he talked to a group in New York and had to explain that this was wheat - they've never seen farms or wheat plants!

Mann then showed photos of the several varieties of potatoes that are sold in the Andes, to which they are native. He couldn’t believe they were all potato varieties! Neither can we! Ridge and furrows system of ploughing, with snow in furrows suitable for potatoes. Europe and eastern USA are more suitable for potatoes than Andes.  This caused a food revolution - Europe could feed itself, for the first time ever.
 
Potato varieties in the Andes!
Suddenly Europe had more stable governments, since there were no hungry mobs. Potato was the fuel of European empires, said Mann. We don’t usually consider the political implications of vegetables; its not something that seems to interest historians.

In the 1840s,  Europeans discovered islands off the coast of Peru with 200 feet of guano (bat and bird dung), which had very high nitrogen content, and were extremely popular as fertilizer. These mounds of guano were mined by Chinese slaves –this was the beginning of a European green revolution.

Potato blight killed million people in 1845, then another million in 1846. Ireland was worst affected. This was the last major famine before the invention of photography.

Indian culinary history is not as well developed as it should be given its culinary greatness. Gujarati traders probably brought in some crops from Africa, not just Portuguese.

China is a country that has to grow rice with almost no flat land and very little water. China has only only 7% of world's fresh water, but grows water hungry crops anyway! Maize is grown all over western China in terraced hills - this began only in the 18th century and is very much an ecological disaster!!!

China was still trying to recover from the introduction of American crops in 1850s. India was politically fragmented, so such crop adoption was not uniform. But everything was and is done top down in China, so a bad political decision can have an impact that lasts quite long.

Malaria was gifted to Americas via the Columbian exchange. Plasmodium, the germ that causes malaria, can hide in liver or spleen of healthy human for years and then suddenly resurge. It hides in red blood cells where immune system cant detect it and spreads all over body.

Central and West Africans have more immunity against Falciparum than any other people. Also against yellow fever. Falciparum thrives in tropics, can't handle temperate zones. During the Colonial era, there was a Parliamentary enquiry in Lodon- why British soldiers died in African territories (but not so much in the Americas)? The answer was lack of genetic immunity against African diseases.

Adam Smith asked why slavery existed? Indentured workers were quite common in Europe until slavery was introduced, which wiped out Indentured Labor. Mann posits that Malarial Immunity helped growth of slavery - living slaves were better than dead indentured workers, and since Africans who had the genes to resist malaria outlasted the white and native American population who had almost no immunity against these diseases, germs and genes played a major role in the continuance of slavery.
 
MS Swaminathan and Charles C Mann at the MSSRF
Dr MS Swaminathan added that most Indian food crops like rice wheat mango are not of Indian origin. Globalization of natural resources and husbandry can be quite beneficial for everyone, not just create a system of winners and losers. He congratulated Charles Mann for an excellent speech and excellent pictures, and the wonderful book 1493.

Gopu’s Notes
1. The theory of Tectonic plates and Pangaea are recent developments in Geology
2. Alfred Russel Wallace discovered a species barrier with no seeming geographic logic, in the islands of Indonesia. This is now called the Wallace line.
3. The discovery of guano islands off Peru is a major part of Thomas Hager’s book The Alchemy of Air, which then goes on to describe the Haber Bosch process for producing  artificial nitrogen fertilizer.
4. Jared Diamond’s book Guns, Germs and Steel examines the inequal epidmeological consequences of one aspect of the Columbian exchange and its ultimate causes. I strongly recommend this book.
5. Carbon dioxide and global warming are the reason why Life (and clouds) exists on earth – as opposed to the barrenness of Mars.
6. On the positive side, Mankind is winning the war against diseases. Almost all diseases are on the retreat. This is wonderful news, which doesn't sell magazines or ads, so it won't make it to headlines or public knowledge.
7. Mann's malarial hypothesis of slavery is quite original. But history may be a bit more complicated than that. Indian indentured labor became quite popular when slavery was finally abolished in the British Empire and its colonies, before abolition in the USA. Slavery was not entirely about farm labour, either.
8. This essay (in Tamil) explains how Egypt utilizes water for agriculture. And perhaps has lessons for India.
9. Dr MS Swaminathan was instrumental in furthering the green revolution brought about by  Norman Borlaug.

News links
1.     The Hindu’s report on this lecture
2.     New York times review of this book 1493

Sunday, 22 January 2017

கம்சிலோவின் உயிரின கணக்கு

Fascinating graph of Life on Earth - this blog in English 

கடல்வாழ் உயிரினமும் நிலவாழ் உயிரினமும் பல விதம் வேறுபட்டவை. உருவத்தில் மட்டுமல்ல, எடையிலும் அவை பிரம்மாண்டமாக வேறுபட்டவை! எடையா?
தாவரங்களுக்கும் விலங்குகளுக்கும் உள்ள வேற்றுமையும் நாம் யாவரும் அறிந்ததே. இந்த ஒப்பீட்டிலும், எடை வேற்றுமை வியப்பானது!

ஒட்டுமொத்த உயிரினங்களின் எடையை எப்படி அளக்கமுடியும்? கருத்து கணிப்பு போல் இதுவும் புள்ளிவிவரங்களை ஆராய்ந்து கணக்கிடும் விவரம். சராசரியாக ஒரு சதுர மீட்டரில், ஒரு சதுர கிலோமீட்டரில் எத்தனை உயிரினங்கள் உள்ளன, அவற்றின் தனிப்பட்ட எடை என்ன, இதனால் ஒரு சதுர கி.மி.யில் அவற்றின் எடை என்ன, இந்தந்த பிரதேசத்தில், நாட்டில், நிலப்பரப்பில், நீர்பரப்பில் என்று கணித்து வகுக்கும் அளவுகள்.

“உயிர்மண்டலத்தின் பரிணாம வளர்ச்சி” (Evolution of the Biosphere), என்னும் நூலை எம்.எம்.கம்சிலோவ் (MM Kamshilov) ருஷிய மொழியில் எழுதி, ஆங்கிலத்தில் மின்னா ப்ரோட்ஸ்கயா (Minna Brodskaya) மொழிபெயர்த்ததை, சில வருடங்களுக்கு முன் படிக்க நேர்ந்தது. மீர் அச்சகம், மாஸ்கோ, 1972 வெளியீடு. டைனாசர் காலம் சென்று பாலுண்ணி காலம் தோன்றி, மனித இனம் பூமியை ஆண்டுவருவது நம் கர்வம் கொண்ட கற்பனை. உயிரினம் மலையெனில் மனித இனம் அதில் ஒரு மடு. ஏன் விலங்கினமே மடு தான்.

உண்மையில், மரங்களே பூமியின் மிகப்பரவலான உயிரினம். பூமியில் முக்கால் பரப்பு கடலும் கால் பரப்பு நிலமும் இருப்பதால், உயிரினங்களும் அதே விகிதாச்சாரத்தில் இருக்கலாம் என்பதே நமக்கு இயல்பாக தோன்றும். இனங்களின் எண்ணிக்கையில் (வகைகளில்) தாவரங்களை விட விலங்குகளே அதிகம். ஜே.பி.எஸ்.ஹால்டேன் என்ற உயிரியில் வல்லுனர் தீவீர நாத்திகவாதி. அவரிடம் ஒரு நிருபர், “கடவுள் இருந்தால் அவரை நீங்கள் எப்படி வர்ணிப்பீர்கள்?” என்று வினவ, “கடவுள் இருந்தால் அவர் அளவற்ற வண்டு பிரியர்,” என்றார் ஹால்டேன். நாற்பதாயிரம் வண்டினங்கள் உள்ளன. மற்ற எல்லா இனங்களை விட, இனவகையில் மிக்க வாழ்வது வண்டு இனமே. .

இதோ கம்சிலோவின் கணக்கு!

நிலம்வாழ் உயிரினம்
எடை
தாவர இனம்
விலங்கினமும் நுண்ணுயிரும்
டன் * 10^12
2.4
0.02
விகிதாச்சாரம்
99.2
0.8

கடல்வாழ் உயிரினம்

எடை
தாவர இனம்
விலங்கினமும் நுண்ணுயிரும்
டன் * 10^12
0.0002
0.003
விகிதாச்சாரம்
6.3
93.7

எண்ணிக்கையில் விலங்கினமும் நுண்ணுயிரும் அதிகமாக இருப்பினும், பெரும் மரங்கள் உயிரினத்தில் தொண்ணூறு சதவிகிதம் என்பது, வியப்பை அல்ல, எனக்கு பிரமிப்பை ஊட்டுகிறது.

Monday, 9 January 2017

Alfred Russel Wallace

January 8 is the birth anniversary of Alfred Russel Wallace. Last year, I was given an opportunity to write this essay for the online edition of New Indian Express by R Venkatasubramaniam. I share this now on my blog, partly named after him. 
-------------

Charles Darwin and Theory of Evolution are famous. But how many know that Darwin was not the only person who discovered either evolution, or its primary mechanism, Natural Selection? How many know of Alfred Russel Wallace, one of the greatest biologists the world has known?

Most of us learn from textbooks in schools. But often, text books, especially on science, are dry collections of facts, which offer neither context nor history to great discoveries or adventures. It is the great failure of poets, novelists and filmmakers, that they rarely laud the accomplishments of great scientists or engineers, even though the world we live in has been dramatically modernized, modified and made a wonderful place because of their superhuman talents and efforts.

Wallace was as great a scientist as Newton and Darwin!
Wallace as a young man

Alfred Wallace was born in England, in a family that was poor but educated. His father died when he was seven. So he joined his elder brother William as an apprentice surveyor. While traversing the countryside surveying land, he was fascinated by plants and began collecting them. Darwin was already famous in England, because he had traveled around the world for five years in a British ship called HMS Beagle, studying biology, and had written a very popular book, “The Voyages of the Beagle.” Darwin himself had been inspired by the travels and adventures of Alexander von Humboldt, a German scientist. Humboldt’s book “Personal Narrative of a Journey to the Equinoctial Regions of the New Continent” caused a sensation in Europe.

In India, even in school, we read about the travels of Fa Hien and Hiuen Tsang, Buddhist pilgrims; ibn Batuta, a lawyer; and Marco Polo, a businessmen. Humboldt was the first modern scientist whose travelogues became famous. The New Continent was America; it was Humboldt’s accounts of the Amazon that awed and inspired Darwin and a whole generation of adventurous Naturalists. (The word science was coined only in the 19th century; before that scientists were called Naturalists or Natural Philosophers). Darwin himself traveled to South America, to the coral islands of the Pacific, to Australia and New Zealand. On the ship Darwin read Charles Lyell’s book on geology, and saw evidence of geological phenomena wherever he went, and understood how much geology influenced biology. He formed several ideas about evolution but did not yet publish them.

The young Wallace went to public libraries and read pamphlets written and printed by popularizers of Natural Philosophy. One book that inspired Wallace was Lindsey’s “Elements of Botany.”

In 1848, an economic recession gripped England; Wallace lost his job. He enrolled in Mechanical College, a low cost school set up by industrialists to educate poor youth. There he befriended Henry Bates, another keen naturalist. They read Humboldt and Darwin and dreamed of voyages to the Amazon and discovering new species. In those days, rich collectors in Europe were fascinated by collections of butterflies, beetles, fossils, exotic plants etc and would pay naturalists good money for rare collections. Wallace and Bates hoped to sell such collections to finance their travel and scientific pursuits. They got a chance to travel to South America. For four years they explored the Amazon and its tributaries, sometimes together, sometimes apart. They suffered from all kinds of diseases, barely escaping death a few times. Alfred’s brother who accompanied them was not so lucky; he died of a tropical disease, and Alfred only found out months later. Wallace meticulous collected thousands of species of insects birds reptiles; drew several thousands sketches, and shipped some to his agent in London, who sold a few. But he did not form any scientific theories or publish any papers.

In 1852, he set sail for England. (Bates continued in South America for seven more years.) Misfortune hounded Wallace. His ship caught fire mid-sea. He lost almost all his collections, painstakingly gathered over four years. Wallace escaped on a life boat with some others, but they almost died of thirst before they were rescued by another ship. Wallace returned to England almost as poor as he left it, but his agent had insured his collection, so he was able to salvage some money.

In 1854, Wallace set sail for Singapore, and explored the islands there for the next eight years. and wrote a book about their biology, The Malay Archipelago. He noticed something strange – the birds and animals of Bali were remarkably different from those of Lombok, though both islands were only fifteen kilometers apart. Species on one island, related to Australian species, were totally absent on the other with Asian species; and vice versa. He realized this was true of several islands. Wallace hypothesized that in the remote past one group of islands had been part of Asia, the other part of Australia, and their geological break up was reflected in their species differences. He drew a line on the map demarcating this geological break; this line was later named the Wallace Line by Thomas Huxley. The field of Bio-geography was born, created by Wallace!

He wrote letters to Darwin, who occasionally responded . His first scientific essay on speciation, excited Darwin’s geology guru Lyell, but neither Darwin nor other naturalists were impressed. 

Meanwhile, Lyell urged Darwin to publish his theory of Evolution, but Darwin delayed. Wallace mailed a second essay titled On the Tendency of Varieties to depart indefinitely from the Original Type, which hit Darwin like a bombshell. Darwin was astounded that someone far away with no scientific reputation had so brilliantly and concisely summarised Darwin’s theory.

He regretted having ignored Lyell’s advice on publishing. He lamented that he had lost his precedence of discovery. His conscience would not allow him to betray Wallace’s confidence. But Lyell and Hooker, another naturalist, persuaded Darwin to let them present Darwin and Wallace’s theories jointly, which they did at the Linnaean Society in June 1858.

It was then that Wallace’s greatest act of decency came shining through. He applauded Lyell and Hooker, and thanked them for not taking away the rightful credit of Darwin’s two decades of work and the fame discovery from Darwin! He even published a book titled Darwinism, which explained evolution more clearly and eloquently than Darwin!

References
1.      Darwin’s Armada, Iain McCalman

2.      Contributions to the Theory of Natural Selection, Alfred Russel Wallace

My Blogs on Biology

1ஆல்பிரட் வாலஸ் கண்டு ரசித்த சொற்கத்தின் பறவைகள் 
2Smt Radhika Parthasarathy's Summary of my book review of Darwin's Armada


4. Plant fossils near Madras
5. SymbioGenesis - Lynn Margulis' Supplement to Theory of Evolution
6. கப்பலோடிய ஆங்கிலேயர்
7. Astounding Statistic - Domination of Land Plants

Saturday, 12 March 2016

Statistics on Biology - please help

Friends I'd like some help collecting statistics. This is also an experiment using my blog as a tool. (I'm also doing this on Facebook). You may remember terms like species, genera, order, phyla etc from school biology. In the comments section please answer the following.
A. What's the highest level of category of Living Things which you can remember?
B. How many subdivisions of that level are there, what are they? List them please. (Not the hierarchy from highest to lowest)
C. Now this is mainly what i want. Look up your son's or daughters science or biology text book. Now list those answers, with your 1. city/country 2. Board of education, abbreviation will do. CBSE, state etc. 3. Class in which your son or daughter is studying. 4. Answers to A and B as listed in that book.
For A & B **Please** don't look up Wikipedia, or biology websites to answer these. I want to know what *you studied* in school, NOT what you learnt afterwards
If you still have some textbook from your school, that will be fantastic.

Sunday, 22 March 2015

The Botany of Mamallapuram

Mamallapuram is famous for its sculptures and monuments of the Pallava era, but its botany is quite interesting.
The native vegetation around Mamallapuram‬ (better known as Mahabalipuram, also called Mallai) is of a category called Tropical Dry Evergreen Forest (TDEF). This is a special kind of forest found along a narrow strip of the coast of Tamilnadu.
Most evergreens are temperate - this is one in the Tropics!
Most evergreens are in rainforests. This one is *dry*, it only rains a couple of months in these parts. The original vegetation had evolved to absorb moisture from the coastal air in the dry months. These trees never - or rarely - shed leaves. One leaf of a specific tree was marked with ink and it was still on the tree fifteen years later!
Prof Swaminathan remarked in 2010 that Mamallapuram has the only creeper (not tree) of the ficus family that he knows of. There are a few other TDEF along the coast of Tamilnadu.
Other vegetation has invaded these regions though.
Udaykumar, a professor of botany from Presidency college, Madras, explained these during the first THT Site Seminar. In this photo, behind him is a creeper called "yaanaikodi" wrapped around a neem tree. "Yaanaikodi" translates as "Elephant creeper" - it is the only vine strong enough to hold an elephant - usually that needs iron chains.
Yaanaikodi - elephant creeper - யானைக்கொடி
The dwarf palm in the centre of the picture below, called ciRReecal in Tamil, is about 150 years old estimates Udayakumar! You can see several of these in Mallai.

Dwarf palm -  சிற்றீச்சல்

"korai" கோரை
 The tree here is called "eerkolli" which can be translated as "LiceKiller" or "Dandruff killer". It's timber is wonderfully sculptuable, and used to be made into combs with very fine teeth, used to crush lice and eggs of lice in hair, before plastic combs and medical shampoos reduced its popularity.

"LiceKiller" ஈர்கொல்லி மரம்

சோழமண்டல தாழம்பூ
This photo is of the last of the Coromandel Thazhampoo (screw pine?) at Mallai.

Sunday, 12 January 2014

Plant Evolution and Diversity

This chart or graph of Plant diversity, I just stumbled upon on a talk about Amborella and the Origin of Flowers, is worth viewing patiently. For the not too scientifically inclined, it can be a delight to just look at the relationship and proximities of different species and how different they are from our daily experience and interactions with them. For example, notice that Tea is closely related to Blueberries; Beets to Cacti; and Coffee, Olives and Tomatoes are on the same branch, while Pineapple preceded Grasses, which include most cereals like Rice and Wheat! 

How, but scientifically would we link Mustard and Papayas, and note that they are more closely related to Grapes than to other spices or Fruits, like Gingers and their cousins, Bananas. 

I wonder how much symbiogenesis plays a role in this branching.



Saturday, 19 October 2013

Symbiogenesis - alternate to Darwin's theory of evolution

In the media, especially American, there is often uproar about Creationism, a christian denial of Darwin's theory of evolution. In the Indian media, biology and chemistry are thoroughly ignored. Famous scientists / public speakers especially Richard Dawkins, thunder away with dogmatic militant atheism, as though Christianity were the big challenge to Darwin & Wallace's theory. The views of people like Stephen Jay Gould, who called religion Non-overlapping magisterium, get muted in the public discourse, and his explanations like 'punctuated equilibirium' are generally unknown, as are recent terrific advances in genetics. Meanwhile, in the last HUNDRED years, an alternate set of theories and ideas have cropped up - symbiogenesis, primarily - that seeks to explain missing gaps and illustrates a brilliant mechanism for speciation, which is stunningly ignored in the media, academia, and even intellectual circles, while they bombard us with incomprehensibles like string theory, dark matter and Higgs boson.

For those interested, here is something scientific, from a wonderful scientist. I wish there were some good illustrated talks on the subject. The article may be hard to follow for those who havent read about it, and even more so for those who defend evolution without understanding its elements- in that field I recommend Alfred Russel Wallace's brilliant book "Darwinism" over Darwin's own hard to follow book "Origin of Species."

http://www.scoop.co.nz/stories/HL200903/S00194.htm

Update: For an introduction to some of the topics discussed in the above article, I recommend watching these videos on Youtube.

I read Nick Lane's book "Power, Sex, Suicide" a few years back. It explains how mitochondria, which have their genome outside the nucleus of a cell, power the cell, help it respire, and pass on their DNA called mtDNA along via the maternal line to the offspring. Basically the book explained the physics and chemistry of the eukaryotic cell - i.e a cell with a nucleus, and how it differs from a prokaryotic cell - a cell without a nucleus. The formation of nucleus and absorption of mitochondria was a non-evolutionary event, in the Darwinian sense.

This video of Dr Nick Lane illustrates some aspects of the book. Excellent!

This is a much simpler and smaller lecture by same author, Nick Lane, but without pictures, sadly.

Saturday, 24 August 2013

Fascinating graph of life

How does life on land differ from life in the oceans? Answer: Dramatically!!

How do plants differ from animals and micro organisms, by the number and mass of species? Even more dramatically! Incredible, in fact.

This is one of the most bizarre graphs I have seen, from a book "Evolution of the Biosphere", by MM Kamshilov, translated from Russian to English by Minna Brodskaya. Mir Publishers, Moscow, 1972.

Life on Land

Matter Green Plants Animals and Micro organisms
Tons * 10^12 2.4 0.02
Percentage 99.2 0.8

Life in Oceans

Matter Green Plants Animals and Micro organisms
Tons * 10^12 0.0002 0.003
Percentage 6.3 93.7


Post script: This is my first HTML hack on my blog, to include the table.