Ancient trees: conserving living heritage for posterity


The Mallanimli Baobab of Orchha, India, the great Banyan tree of Kolkata Botanical Garden, the giant red woods of California, the ancient Ginkgos in China, the mighty dipterocarps in Malaysia or the eucalypts piercing the Australian landscapes, all these trees keep mesmerizing us not just by their larger than life presence, but also by their ancient links with our forefathers. These widely known woody giants not only instigate our romanticism about nature, but they also remind us about the past features of the landscape and peoples’ affection towards it. Historically, ancient trees in many areas are symbolic of socio-religious links humans had with nature. They are present in the forest, pasture, rangeland, valleys and agriculture lands reflecting local land use decision, and cultural profile of the communities. But, how to define ancient or old trees? There is no universal definition for ancient trees except few visual clues. They can be characterized by their wider trunks (compared with other individuals of the same species), and low, fat and squat shape; however, it could be specific to species, site and environmental conditions ( Their presence in diverse ecosystems across tropics and temperate indicate wider tolerance to environmental changes and acceptance to a large number of communities.

In India, scores of old growth trees are highly venerated in cultural and religious practices as evidenced in anecdotal resources. Moreover, their association with mythological stories, historical events, andSculpture depicting Bodhi tree social activities are widely covered in the literature. The celebrated examples are Ficus spp. (Ficus religiosa (pipal), Ficus benghalensis (banyan)), Mangifera indica (mango), Tamarindus indica (tamarind), Shorea robusta (sal) (Upadhyaya 1964, Gupta 2001) (Figure 1). Their antiquity mostly felt in religious institutions and sacred natural sites where they are an integral part of the religious architecture irrespective of diversities of faith. There are Stalavrikshas in temples of Tamilnadu, Sai Baba Neem in Shirdi, Maharashtra, Panchavati in Nasik, Maharashtra, great banyan tree at Natna, West Bengal, Pipal tree at Jain Dilwara temple, Mt. Abu, Rajasthan, Mulberry tree at Joshimath, Uttarakhand and countless other members occupy our religious landscape. Sometimes, these trees are places of worship or older than the formalized worshipping places. Graveyards and cemeteries in India also have their own component of tree vegetation too where due to various taboos disturbance is less and our green grandparents can survive (Mango trees in Park St. Cemetery, Kolkata, Chinsurah Dutch cemetery, West Bengal). Remember our childhood ghost stories. Old spreading banyan trees with their spreading branches, hanging aerial roots, and dense foliage, were favourable adobe for our rural area ghosts. Those entangled branches with sparkling fireflies and roaming bats at dark night were scary enough for any lone passerby. The daytimes presented more of a pleasant picture of such trees, in singles or clusters, may be ficus or neem, mahua or mango, Alstonia or bakula in serene landscapes, often nearby village ponds. Cumulatively these practices or beliefs act as a protective shield for old trees (Figure 2).

Leaving apart the literature, many of us would fondly recall the existence of old banyan/pipal/neem/mango trees in our surroundings which were not only our favourite playgroundAncient trees at protection near temple and graveyard but also a remarkable landmark for multiple purposes for all walks of people. Examples can be drawn from our daily life, a landmark for someone’s house or associated with places of our daily amenities like laundry, tailor, grocery shop, the fruit seller, bus stop, local market place etc. it may be a place where locals get together in evenings or rendering cool shade in scorching summer for humans and cattle. Except for places with religious and social importance, often they are found in private property as a symbol of family’s proud possession through generations, or in not so easily accessible areas like mountainous terrain. With the passage of time, many of them received the heat of development in the name of city expansion, road widening, power line or dam construction and wiped away from our landscape.

The common notion about rural landscape with its greenery studded with magnificent heritage trees, seems to be a feature of past in the near future. It is due to modernization of agriculture and rapidRoadside Acacia sp. plantation Compensatory afforestation program in rural landscape socio-economic changes we are losing our rural plant diversity which is often replaced by economically important species be it timber or cash crops. A pertinent example can be cited from road network establishment program. Aimed at greater connectivity and economic prosperity of even interior villages, the implementations are ecologically and environmentally insensitive in most places of India.  Large numbers of good old trees are cut without giving a second thought and as compensation, we are getting Acacia, Eucalyptus, Casuarina, Peltophorum spp. For rural folk, these trees are financially acceptable as they grow fast, people are getting money for their maintenance and even for cutting and selling (Figure 3). On the flip side, nobody concerns about the soil quality deterioration, disruption in nutrient cycling, adverse impact on local fauna. Even for the sites, where ancient trees are venerated by people and are protected, their surroundings are not supportive of their existence in the long run. Activities like trimming branches, curtailing root growth and water percolation by cementing the base, temple/mosque/house/shop construction etc. cumulatively affect tree health and its future generation.

Urban landscape presents a more complex scenario mostly with a negative notion. Intense urban housing and transport infrastructure, space crunch, heterogeneous community, multiple lifestyle demands and political wills are major drivers for green space management. Many a time, the spreading canopy and apparent clumsiness of the old tree does not fit with the urban criteria of green space beautification. Obviously, felling and uprooting of old trees disturb us, but their absence from our lives is barely felt owing to a lack of awareness on their role in nature. Above all, environmental awareness is still at its nascent stage in urban society, the consensus is often restricted to pollution, solid waste management and tree planting, where the number counts, the species choice depends on what survive easily and grow faster.

In view of this socio-cultural and spatial background, the obvious questions are what is the importance of having an ancient tree in a landscape? Aren’t we doing plantation, establishing green place and following other sustainability measures? To seek the answers, we have to explore multiple aspects of human cultural history along with evidence-based ecology and environmental perspectives. Ecologically, ancient trees are Pandora’s box for us though in a positive note.  Careful observation can reveal interesting sights of bats hanging inversely from the trees which are an important mediator of pollination and dispersal for many species, similarly, beehive may pose danger for some but they areAncient trees are supporters of many lives the backbone for agri- and horticulture, without them, big industries can fall apart (Figure 4). You see a flock of birds resting on the trees, perhaps they are the long-distance flying birds or migratory birds who use these trees as halting place in their journey. Look into the caterpillar, insects, ants, grasshoppers, scorpions these members need a very minimal resource for their survival, an old tree is like a grandfather for them from where they are getting food, shelter and congenial atmosphere for home. Last but not least important, a big old tree means storage of carbon dioxide (a major greenhouse gas) in different forms for many years, therefore, contributes to keep our atmosphere clean. One can argue that these services are common to all well-grown trees, but for ancient trees they are the time-tested long-term establishments under different climatic and anthropogenic scenarios, which definitely have experience values.

Looking into the cultural history, trees demarcate human’s association with a particular place. For many of us with a rural or semi-urban background, nature had played an important role in our mental growth during the formative years. The gigantic and spreading appearance of the old trees are responsible for both the feeling of admiration and fear which perhaps the first lesson to understand the mightiness of nature. Simultaneously, observing the flock of birds and their nests, beehives, bats, squirrels, caterpillar, ants and countless other life forms under the big umbrella of the ancient tree also teaches us the lesson of inclusiveness. Likewise, our socio-religious activities (eg. marriage, naming ceremony, social lunch, festivals, get-together, after death rituals) centered around the tree build up the connection between the people and tree, in a broader sense with nature. Many indigenous communities relate themselves with a particular tree, a sign of cultural identity for them. Example can be drawn from pimpleys of Maharashtra (pipal or Ficus religiosa), Gaadas of Karnataka (kadamba, Neolamarkia cadamba), Umariyas from Madhya Pradesh (umar tree Ficus racemosa), Dhanik clan of Madhya Pradesh (dau tree, Anogeissus latifolia), Santal from Chotanagpur plateau (sal tree, Shorea robusta). In brief, consciously or sub-consciously ancient trees are entangled with our lives.

Old trees are omnipresent in literature, arts, religion, traditional forms but comprehensive studies on their environmental existence are still underexplored. Except for documentation and public outreach materials they are almost divorced in our research domain. Studies on old trees to evaluate their role in ecosystem especially in semi-urban and urban landscape are in dire need. On the same note, environmental awareness programs focusing on these ancient members should involve and sensitize people about their ecological and social values. The living heritage, the band of our green and mighty forefathers, should be protected for our biological and mental well-being as well as for posterity. 


The author is thankful to Prof. M.D. Subash Chandran, Centre for Ecological Sciences (CES), Indian Institute of Science for reviewing the manuscript for its improvement and Dr. Avik Ray for his comments on the earlier versions.



  1. Gupta S.M (2001) Plant myths and traditions in India. Munshiram Manoharlal Publishers Private Limited. ISBN 81-215-1007-4.
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About Author:

Rajasri Ray



Nutritional potentiality of Makhana cultivation in wetlands and water body of India

Mothers and grandmothers are worried about the health of the children, there are continuous discussions on how to develop a healthy diet for them, there are endless discussions during pregnancy what to eat and what not, so that both mother and baby will be physically fit. Similarly, work-loaded people are looking for some good options to keep themselves stress-free and full of energy. Above all, profit-driven business groups also formulate new recipes in terms of health and nutrition. As a result, our market is flooded with all kinds of nutritional drinks and foods. So the obvious question is how important nutrition is. The state of health of a person is influenced by the consumption and utilization of nutritious food substances, indispensable for a qualitative life and well-being. Therefore, the nutritional status is managed by the balanced food intake and normal utilization of essential nutrients including protein, vitamins, carbohydrate, fat, minerals and electrolytes. In the developing countries like India the economic factors, food habits and lack of nutritional guidance together lead to a high prevalence of malnutrition (deficiency of sufficient nutrients in the body). And protein is the most expensive nutrient which lacks more commonly than any other nutrients (Maura, 2002).

India is blessed with a wide variety of foods (both conventional and unconventional) owing to its rich social, cultural and natural fabric. One such example is Makhana, also known as black diamond, rich in protein and vitamin but low in fat and cholesterol content ideal for modern nutritional demand. Makhana is cultivated within wetlands (transitional zone between terrestrial and aquatic ecosystem), which support a stable aquatic ecosystem with rich biological diversity.

The mother plant, Euryale ferox Salisb. (Makhana) under the family of Nymphaeaceae is a large water lily and commonly known as gorgon nut or fox nut. Morphologically it is a rooted submerged macrophyte with an attached rosette of spiny floating leaves (Figure 1). It is a widely grown macrophyte in the stagnant perennial water bodies, containing frequently waterlogged soil and the water table at or near the surface. Makhana is usually grown in the wetlands, swamp and marshy tracts and nayanjulis (roadside water bodies) during the rainy season. Makhana is a native plant of South-East Asia, China, Japan, Korea, and eastern Russia and is well-distributed all over the world. In India, it is distributed in northern India spanning across the states of Bihar, Jammu & Kashmir, Assam, Manipur, Tripura, Eastern Odisha, Madhya Pradesh, Uttar Pradesh and Rajasthan. In Jammu and Kashmir, Makhana was cultivated as an ancient natural crop, commonly known as juwar. Thereafter, it has expanded in entire north India including eastern and western states. Makhana cultivation is widespread in the north-eastern part of Bihar (Mithilanchal) that accounts for approximately over 80 per cent of India’s total production of Makahana (Chaudhuri, 2006).

Wetland roofed with Makhana

Makhana is characterized with gigantic floating leaves ranging from 1 to 2 meter. The rounded leaves (uppermost part) appear to be green whereas the colour is deep purple on the reverse (lower-most) and covered with numerous spines on all the surfaces (Figure 2a, b). It has cluster roots of fleshy and fibrous nature. Makhana has much thicker roots, as long as 40 to 50 cm. This unique aquatic plant is having bright purple-blue flowers, up to 4 to 5 cm long, with white petals in the centre, and long pedicel (Figure 2c). It is an absolutely seed propagated plant, which produces 15 to 20 rounded, spongyFigure 2. a) upper and b) lower side of the leaf; c) Makhana fruits, having sharp prickles. Each fruit consists of a number of seeds, small in diameter (less than 2 cm), having a hard outer cover around the white edible part. The seeds are finally processed into the edible form, which is white and starchy in nature i.e. makhana (Kumar et al.2011, Kumar 2017). In India, the wetlands and water bodies constitute a special ecosystem by supporting a notable presence of Makhana over large tracts with a shallow depth (1 to 1.5 meter or 4 to 6 feet). Several pockets of the water bodies are progressively roofed with this hydrophyte especially at the monsoon months when the water is at its peak.

Makhana is cultivated as a seasonal annual crop and dies out after the fruits mature. The seeds are first broadcasted (sowing) in the surface water of wetland during the post-monsoon period Initial phase of germination (November-December) (Figure 3). The germination process starts in the month of March and the plant comes out above the surface water. After one and half months (30-45 days) from the flowering period, the fruits get fully matured and the ripen seeds start bursting during the month of July-August (Figure 4). The seeds are generally harvested as well as collected in the last week of July or first week of August, following several rounds of practices. Being a labour intensive crop, Makhana cultivation includes a number of processes like harvesting, collection, cleaning, rubbing, storage, packing and marketing. The entire process of Makhana practice involves a large number of labours. Especially, labourers involved in seeds collection get a good wage, which ranges from Rs. 500-1000 to Rs.1500-2000 per day, depending upon the location.

Makhana cultivation within the wetlands is associated with numerous economic benefits. There is a scope in revenue generation by practising makhana in a vast area, where the major cost of about 84% is consumed in Makhana processing, as compared to the cultivation cost of only about 15% (Kumar 2017). Furthermore, Makhana cultivating wetlands and water bodies are utilized as an ideal reservoirMakhana cultivation in wetlands at mature stage for culturing diverse fish fauna in the intervening period between two successive Makhana crops. The decomposed plant parts of Makhana accumulate organic detritus in the bottom surface, which are consumed by the bottom-dwelling fish fauna in the wetlands. The Makhana cultivation along with fishing practice has enormous socio-economic values, which provided economic sustenance to the settlers residing around.

Apart from the economic importance this aquatic macrophyte play a substantial role in the local socio-economy in the form of having nutritional value and medicinal importance. The calorific value of Makhana compares well with staple food materials such as wheat, rice, etc. and supports to meet the great demand for the fish and vegetables of the fast-growing population in India. Makhana seeds (Figure 5a, b) are highly rich in vitamin, protein and mineral contents like magnesium, potassium and phosphorus, but low in saturated fats, sodium and cholesterol. The edible part of the seed contains moisture (12.8%), protein (9.7%), carbohydrates (76.9%), minerals (0.5%) and a very low amount of fat (0.1%) (Anonymous 1952). Moreover, its health benefit is superior to dry fruits and used in making delicious dishes and desserts, which are very popular throughout India. Along with having nutritional value, Makhana is popularly used in the medicinal purposes against several human ailments like respiratory, circulatory, digestive, excretory and reproductive systems.

Makhana is considered as a mandatory ingredient in the baby food in most of the countries and itMakhana seeds & finished product serves as an ideal food for the old people, because of having rich protein but low-fat content. Makhana is considered excellent during pregnancy because of having a low glycaemic index and other nutritional assets as well.

India, being one of the developing countries of the world, agriculture is the mainstay of the country’s population as well as the economy. Therefore, efforts are being made to spread this distinguished aquatic crop to other suitable areas, so that the wetland based economy in the form of Makhana flourishes as well as gives a considerable amount of cushion to withstand the impact of poverty. Local administration and Government should take some effective steps in order to extend the percentage of cropped area under Makhana cultivation and to improve the scientific knowledge regarding the beneficial effects of Makhana both in terms of health and economy. Furthermore, an attempt is required to mechanize the various components of Makhana cultivation starting from germination to seed collection and for the horizontal expansion of cultivable area (Kumar et al. 2011). India is associated with a number of wetlands, which are agro-climatically suitable for Makhana cultivation. Thus, conservation of these economically viable taxa, with high nutrition value, is desirable from the perspective of biodiversity within the wetlands.



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  3. Anonymous (1952) The Wealth of India. Council of Scientific and Industrial Research, New Delhi
  4. Kumar A (2017) Cultivation of Makhana, Euryale Ferox for potential utilization. Flora and Fauna: 316 – 318.
  5. Kumar L, Gupta V, Jha B, Singh I., Bhatt B, Singh A (2011) Status of Makhana (Euryale ferox Salisb. cultivation in India. New Delhi: ICAR Research Complex for Eastern Region.
  6. Maura EGD, Passos MCF (2002) Importance of the nutritional status for the interpretation of nuclear medicine examinations. Brazilian Archives for Biology and Technology 45.
  7. Wunderlich S (2013) The importance of appropriate nutrition assessment and nutrition education for older adults. Journal of Nutrition and Food Sciences 3:5.

About Author:

Diyali Chattaraj


Wild uncultivated edible plants of India

Kalasin Province, the largest and poorest part of Thailand, is located in the Korat Plateau. In a sleepy village of the province, Watcharapong wakes up in one early morning, goes out to the forest to grab some Phak saap or Nang noon (local passion fruit – Adenia viridiflora) from a nearby tree of the forested patch. These give him vital support during his untimely hunger pangs. Fresh harvest from the plant is a boon from mother nature. Now travelling twenty-five hundred kilometres away from Watcharapong’s shelter, there awaits another story. We shall meet Rabeya of a nondescript village near Fulbaria in Mymensingh district, Bangladesh takes her winnowing basket (Kulo) to collect and segregate some dheki shaak, or bathua as her leafy green to supplement her luncheon. She has already sent her son to the local Jheel (small water body) to get some shaluk (water lily or Nympahaea nouchali leaves and tubers) that makes a tasty side-dish. Further away, tucked in tree canopies of the forested land of Abujhmar, that falls in the Chhattisgarh state of India. Gonds, Muria, Abuj Maria are the aborigines of this region for time immemorial and they rely on jungle food. Many a fruit they gather, tendu (Diospyros melanoxylon) is one of their major harvests, they also collect tendu leaves but for making bidi – poor man’s cigarette. So, it is not an unusual encounter with a gathering person in rural south or south-east Asia, who used to spare some time from daily chores to browse and collect wild and uncultivated plants from a solitary tree, or from nearby forest patch, fringes of agricultural fields, or from homesteads.    

A rich biocultural heritage also implies a diversity of means to explore and utilize the natural resource. A great leap from one cultural geographic region to another may or may not change the species assemblage, but the practice of wild edible harvest prevails across countries and continents, Asia to Africa and so on. Unfortunately, gruesome debates in academia that often focus on food production indulging on formal agriculture but largely ignore the ubiquity of wild food spectra. While they are an alternative and low-cost source of calorie and nutrition, especially for economically down-trodden groups. Thus, still could be a ray of hope for many and reserves an untapped potential to nurture that has not been fully realized in our food policy.

Perceiving the utmost necessity of this topic on food security, we introduce an additional section from this issue that takes in various wild and uncultivated food plants. We wish to engage our readers with the various kinds of wild food; by wild food we mean they are not under formal cultivation, but may be under minimal management and have been consumed for generations. Our research suggests there are more than thousands or so edible plants in India utilized locally or regionally or even across much broader geographic realms. It underscores the exercise of eating wild food has not been a sporadic habit, but ingrained in our culture. We also observe significant sharing of our traditional wisdom related to wild edible gathering among communities perhaps owing to cultural diffusion. So, let us celebrate our knowledge of nature, natural resources, and its sustainable use.

Part 1

Adenia hondala

Family: Passifloraceae

A woody climber from the family of much familiar ‘Passion fruit’ that crawls over other trees and refuges a plethora species including caterpillars of many butterflies. It has palm-shaped leaves with large circular sessile glands between the lobes. The roots are tuberous in nature, though toxic, possess medicinal properties. This scrambling plant is usually found in the deep interiors of the semi-evergreen and moist deciduous forests of the Western Ghats of India and Sri Lanka. The tribes of Pania, Mullukuruma, Kuruma, and Kattunaikka use the leaves, cook with other greens and consume it. The shoots are also eaten but the flowers as food have not yet been checked out. Though the tribes regularly use the leaves for cooking the importance of the plant as a food substitute is not popular. The commercial cultivation is also another less-explored area. The remotely distributed plants in the deep forests of Western Ghats limit the usage as it demands arduous walks from the tribal settlements. In India, the culinary use has been reported from the Hassan district of Karnataka and the Wayanad region of Kerala. The plant is known as ‘vidari’ in the Karnataka region and ‘Koombi chappu’ among the tribes of Kerala. The wild food enthusiasts and chefs may use the recipe of the tribal people as the base for further innovations as the plant’s medicinal and healing properties especially as a pain reliever have been well recognized in Ayurveda and Folk medicines.

Adenia hondala (Koombi chappu)

Cycas circinalis

Family: Cycadaceae

Commonly known as ‘Cycads’, they are little different from our flowering neighbours as they belong to a primitive group of plants, i.e., gymnosperms who came relatively early on this earth. Cycads are quite common ornamentals in urban gardens but one of them Cycas circinalis is conspicuous in the traditional diet charts. Endemic to peninsular India, this plant is distributed in the states of Kerala, Karnataka, Tamil Nadu and in the south of Maharashtra. The plant is popularly named as “Queen sago palm”. The flour, prepared from the dried seed, is commonly known as “eenthakka podi”, a popular substitute of rice flour among the indigenous communities in Kerala. In Pathanamthitta district, endosperms are separated from seed, dried, and powdered to make flour for preparing various delicacies. Moreover, the Kadar tribe of Thrissur uses the underground part (“Eenth”) as food. Irulas of Pillur valley, Tamil Nadu, use the tender leaves and shoots as a vegetable (known as “Enthu”) in their daily food intake. The same habit is also found in Palliyar tribe of Madurai and Tirunelveli districts of Tamil Nadu, where the plant is known as “Paereenji”. The plant is a forest dweller therefore, naturally propagated, but habitat destruction and rampant bark extraction pushed it to the endangered category. Till date, no organized cultivation for the plant has been reported. A recent initiative is taken by CSIR-NBRI, Lucknow for Cycad species conservation in India by establishing Cycad Conservation Centre at CSIR-NBRI Botanic Garden.

Cycas circinalis (eenthakka podi)


Dendrocalamus strictus

Family: Poaceae

This giant grass family member belongs to the great league of ‘bamboos’. Interestingly, it is also infamous in other names, such as male bamboo, Calcutta bamboo or solid bamboo perhaps indicating its sturdiness. Although the plant has been highly valued for making house frames, tent poles, scaffolding, bullock carts, and fences its various edible parts, young shoots, seeds, flowers, underground parts are popular among the tribes and non-tribes alike. The tribes like Gond, Kawar, Nagesia, Oraon korwa, Pandokodaku, Khairwar, Majhwar communities of Chhattisgarh use this plant for the edible leaves and shoots. The plant is called as ‘bhans’ in this area. In the Mayurbhanj district of Orissa, the tribal groups like Santhal, Kolha, Bathudi, and Gond use the leaves, seeds, and shoots as a good source of nutrients. The local names include dongri bans, salia bans, banso, and bans. In Uttarakhand, especially in the Lohba range of Kedarnath forest division in the Garhwal region the flower and the underground parts of the plant are also used among the local communities. Young shoots are cooked and consumed widely in Coorg and Malnad region of Karnataka. The shoots are steamed and salted to be eaten raw. Pushcarts filled with the delicacy are a very common scene in many parts of South India. The food from bamboo remains incomplete without a word about north-eastern India. Perhaps most widely referred use of bamboo is from the seven sisters of India. Assam, Manipur, Meghalaya, Arunachal Pradesh, and the rest of the other states have their variety of sumptuous dishes from young bamboo shoots.

The seeds are used to substitute grains especially when you are keen on your calorie intake. These are used to make a variety of dishes where rice is used. The ‘kheer’ made using the seeds are available across the restaurants of Kerala and is very popular during the harvest festival ‘Onam’. The ‘payasam’ is made using jaggery and milk along with Dendrocalamus seeds. In addition to this, the rural places of south India bake rice with coconut to make steamed cakes or ‘puttu’. Nowadays, being a trendy food it is available in many e–com platforms, organic shops, and dishes are common in many cafeterias in south India.

Dendrocalamus strictus (bhans)



Dimocarpus longan

Family: Sapindaceae

A small yellowish fruit, a litchi in disguise, that may confuse many. Yes, its resemblance to litchi has earned him adorable names, Naga Lichu, Tokra, Kath lichu and Mirgoch among the locals in the state of Assam and in Garo Hills, Meghalaya. In West Bengal, the fruit has a local name as Aansphal, a common surrogate of litchi. The fleshy aril is also cherished raw by the locals of Uttara Kannada, Karnataka. Dimocarpus longan, commonly known as Longan, is a tropical tree of soapberry (Sapindaceae) family that also includes its close kins e.g., litchi, rambutan, korlan. The plant is common in tropics of South Asia and the fruit has white fleshy aril sweeter than the common litchi. The black seed peeps through the white flesh and looks like a pupil and so-called ‘dragon eye fruit’. However, largely owing to rampant logging in recent past the natural populations have dwindled to a great extent and it is now near threatened, although informal horticulture is practised at many places. History says that certain cultures have a long tradition of use (especially in China) but its wider acceptance has begun only recently. There are a few farmers who cultivate these fruits in the southern part of India as the fruit is used for treating insomnia, stomach pain, and dementia. Regarding the increasing cultivation area and increasing quantity of longan fruit, attempts have been taken in India as well. In the northern Bihar, longan cultivation has been started experimentally in Minapur, Mehsi, and Kanti among litchi growers. The modern culinary experts even use the fruit in dried, canned, and other processed forms. The dried flesh of the fruit is available in all supermarkets in India or via e-com stores serving processed foods.

Dimocarpus longan(Aansphal)

Glimpses Of Nature And Culture

Cannabis sativa: The keeper of heritage

The word “Cannabis” is not familiar to us except those who are accustomed with plants and narcoticCannabis sativa: The keeper of heritage products. However, by hearing its popular name “Ganja” or “Bhang” we can almost immediately relate ourselves with the intoxicated hallucinogenic liquid, which many of us tested during festivals. Although it has many other uses around the globe the plant as a construction material is something worthy of mention. Cannabis has another identity as “hemp” which is well known internationally for its fibre. Hemp fibre has a ubiquitous presence in coir, fabric, paper and automobile industries. However, a new dimension has achieved in the form of “hempcrete”, where hemp fibre and it’s woody core (hurd) is used with a lime-based binder to form a concrete-like substance, a very useful constituent for green architecture. Europe is already in that track and the United States is also following.

Interestingly, India had that practice quite long ago, back in 6th century A.D. The famous delighting caves of Ellora, a world heritage site, situated near Aurangabad, Maharashtra had partially built upon hemp-based construction material. Research studies conducted in Buddhist cave no. 12 found that interior clay plaster layer on the wall had Cannabis plant parts as components. The ancient clay plaster sample was analyzed in the laboratory using various sophisticated techniques, such as scanning electron microscope (SEM), stereomicroscope, and Fourier transform infrared spectroscopy (FTIR). Researchers have identified pieces of shoots, fragmented leaves, and flower of Cannabis plant from the samples. It has been suggested that Cannabis was used as a thermal insulator and strength increasing material for plasters. The interior of the cave had a pleasant microenvironment owing to thermal and sound insulation property of Cannabis. It is still unknown whether this psychoactive plant had any role in diet or recreation of the inhabitants but its role as a comfort builder is quite certain. So, respect our green keeper of heritage.

Source: Singh M. and Sardesai M.M. (2016) Cannabis sativa (Cannabaceae) in ancient clay plaster of Ellora Caves, India. Current Science 110 (5):884-891

Photo: Avik Ray,

Collector: Rajasri Ray


Honey, I blew up my tummy!!

How far can you go for your honey? Will you like to store some in your abdomen so that it can be used later? That is exactly what some ants of genera Myrmecocystus, Cataglyphis, Melophorus, Leptomyrmex, Plagiolepis   Prenolepis and Camponotus do. These specialised, sterile worker antshoneypot ants (also called honeypot ants, repletes, plerergates, or rotunds) serve as living larders (cool storerooms) for other members of their colony. Worker ants feed the repletes nectar upto the point their abdomen swells up with golden, sugary liquid and becomes sedentary. The repletes’ hard dorsal sclerites (stiff plates) are connected by a softer, flexible arthrodial membrane. This membrane expands widely to make room for the liquid when the abdomen fills.

They are used as source of nutrients by other ants in the colony when food is scarce. For getting the stored liquid, the worker ants poke and prod the antennae of honeypot ants a bit. This makes the rotunds to upchuck the stored liquid from its crop (a thin-walled expanded part of the alimentary tract for storing undigested food). They are so lucrative as resource that ants of other colonies may also raid and plunder the repletes and enslave them!!! Honeypot ants namely Melophorus bagoti and Camponotus spp. serve as local delicacy among indigenous Australians who use these as a source of sugar. These ants inhabit the desert and other arid environments of Australia, southern Africa, southwestern part of the United States’ and Mexico.

Photo: Wikipedia, Alamy



 It’s all a Fishy affair of dynasties

Fish, not fried or curried, not on a plate, but mounted on a head-gear worn by high-rank militarymahi-ye maratib or Fish of Dignity officials of Mughal dynasties who had won emperor’s favor for their valuable service. So, unfolds the fishy story of mahi-ye maratib orFish of Dignity’ which once used to physically represent as a golden fish or an elongated fish head. It was extravagantly exhibited at royal functions and worn in royal processions by the noblemen who had been so awarded. However, the credit does not go solely to the Mughals, scholars say it has been generously awarded to warriors for their valor by Muslim rulers in India, be it Lucknow Nawabs, Delhi Emperors, or Deccan Sultans. Further back in time, there has been a long legacy of the fish emblem in pre-Islamic and Islamic cultures of the Middle-east and South Asia. The presumed origin traced to Persian king Khusru Parviz who instituted while ascending his throne around six hundred AD. Intuitively, from Persia it would have traveled and taken a longish sojourn in South Asia, was eventually assimilated into the local culture.

Mughal Emperor Akbar happened to be a judicious person and granted mahi-ye maratib selectively, but the tradition eroded from Bahadur Shah, and the honor had become less discriminating. After Mughals, it was in Lucknowi culture, where the fish was adorably absorbed and metamorphosed into a decorative motif widely incorporated in the artifacts, ornaments, or other objects. In course of time, the fish duo became almost a signature of Lucknowi nawabs. In physical appearance, it was a pair of fish arranged head-to-head so that their curvilinear bodies formed almost a circle, but it had also sparked blossoming of innovative variations. The fish-pair appeared in a vast range of objects of art or on the items of daily chores, from medals, throne chair, punch daggers (Katar), presentation cup, to wine decanters, ornaments, plates, bowls, etc. The emblem became so culturally entangled that it was often used as the primary design in Lucknowi bidri-ware (metalware made of a zinc, copper, and lead tin alloy), even in post-Nawabi era.

So, imagine…..a fish duo had once infectiously wooed the dynasties but not luring their taste buds, but relentlessly making their feisty presence in the art and culture.

Source: This Blaze of Wealth and Magnificence: The Luxury Arts of Lucknow and The Use of Flora and Fauna Imagery in Mughal Decorative Arts and by Stephen Merkel

Photo Source: Los Angeles County Museum of Art (LACMA),

Collector: Avik Ray

Weaver ants, weaver ants…. weave, weave, weave …and ……. save our mangos, guavas, lemons…..

Meet the queen, Ms Oecophylla longinoda, her workers and children. They live high on tree canopiesOecophylla longinoda: Weaver ants in the far-away savanna ecosystems and rainforests of the sub-Saharan Africa. They are not arboreal but make nests in trees stitching many leaves together using the silk exuded from their larvae. A similar large number of nests makes up their colony between which they tend to enjoy a stroll or a faster stride. Yes, they are the weaver ants of the tropical Africa and they have a very closely related cousin (O. smaragdina) living in the south and south-east Asian countries.

But, that is not just the reason we should be happy to meet the queen and her kids. Their ecological role is immense in a horticultural landscapes of the sub-Saharan Africa. They help to deliver the juicy and tangy fruits on our plate. But, the immediate question pops up, how a tiny creature can be such a philanthropist?

The answer might not be too apparent and linear, but these predator ants play a crucial role in maintaining the food chain. They are great enemies of fruit flies that voraciously feed on many African fruits, e.g., mangos, cashews, citrus, guava, and many more. The ants release an array of semiochemicals that deter insect herbivores, particularly tephritid female fruit flies. Not merely that, these weaver ants are also one of the ablest predators of arthropods in perennial tropical tree crops.

Therefore, menacing populations of fruit flies can be biologically controlled by generalist predators like Oecophylla species, naturally and without applying any harmful chemical killers. It also compels us to fathom how biodiversity is important to produce our food and in saving our food systems.

Source: Vayssières, J.F., Offenberg, J., Sinzogan, A., Adandonon, A., Wargui, R., Anato, F., Houngbo, H.Y., Ouagoussounon, I., Diamé, L., Quilici, S. and Rey, J.Y., 2016. The use of weaver ants in the management of fruit flies in Africa. In Fruit Fly Research and Development in Africa-Towards a Sustainable Management Strategy to Improve Horticulture (pp. 389-434). Springer, Cham.

Photo Source: [Muhammad Mahdi Karim, GFDL 1.2,, Charles J Sharp (CC BY-SA 4.0 (]

Collector: Avik Ray


Last Ice Age: understanding Earth’s climatic history

With the threat of global warming and unpredictable climate looming over our heads, it is imperative that we understand the past climatic history of our planet to make any predictions about the future. Earth has had a violent climatic past, undergoing repeated warming and cooling phases. A long period of global cooling is known as an ice age. Earth has faced at least five major ice ages characterized by periods of global cooling and permafrost (permanent ice throughout the year) (Hewitt 2000). During an ice age, the polar and continental ice sheets along with the glaciers expand and cover large portions of the planet (Hewitt 2000) (Figure 1). Even within an ice age there are cycles of extended periods of global cooling, termed as “glacial periods”, punctuated by shorter intervals of a warmer climate, termed as “interglacials” (Hewitt 2004; Bintanja et al. 2005). We are currently living in an ice age which the scientists have named as the “Quaternary”.

The current ice age began ~2.58 million years ago with the beginning of the formation of the Arctic ice cap. For the last ~2.58 million years’ earth has undergone multiple cycles of glacial periods and warm interglacials (Hewitt 2000). During the glacial period, ice-sheets cover large portions of the northern and southern hemisphere and global temperatures fall by as much as 8 0C. As most of the water is locked up in ice during this period, global sea levels fall by up to 120m connecting various land masses especially in the Southern Hemisphere (Hewitt 2004; Bintanja et al. 2005; Jouzel et al. 2007) (Figure 2). However, during the warmer periods or the interglacials, ice retreats and the global sea levels rise to the present levels. We are currently in an interglacial period, which began ~15,000 to ~10,000 years ago. Interestingly, the initial glacial-interglacial cycles lasted for about 41,000 years, whereas now the cycles last for ~100,000 years and are much more pronounced (Hewitt 2000; Hewitt 2004). Extent of ice in Eurasia during the Last Glacial MaximumAlthough, the theory of ice age was accepted in the late 19th century, the main reason for the occurrence of the ice ages are not completely understood. It is suggested that Earth’s axial tilt and its interaction with ocean current, atmospheric composition, distance from the sun and solar output are important drivers of global shifts in climate (Hewitt 2004).

Quaternary glaciation has had a strong impact on the world’s biodiversity and is especially well documented in the Northern hemisphere (mostly in North America and Europe). For example, during the glacial periods, large tracts of Europe were covered in ice (Figure 1) and UK was connected to continental Europe by land bridges. Whereas in North America ice sheets covered Greenland, Canada and northern parts of US. As ice covered most of the land, most species were forced into small pockets of habitat. These suitable habitats are known as “glacial refugia” (Hewitt 2000). Location of know glacial refugia for various fauna and flora in Europe during the Last Glacial MaximumFor example, in Europe during the glacial period, most species retreated to the Mediterranean basin and then expanded north only during the interglacial period (Hewitt 2000). The Iberian Peninsula (Portugal and Spain), Italy and Balkans were important glacial refugia for many species in Europe (Hewitt 2000) (Figure 2). Only when the ice retreated, most of Europe was recolonized. This occurred multiple times in the past 2.6 million years. Multiple such contraction and expansions have led to divergence within many species as different refugial populations remained isolated for prolonged periods before getting reconnected during interglacial intervals (Hewitt 2000). For example, the repeated cycles of climate cooling and warming led to the gradual divergence of western and eastern populations of meadow grasshopper, brown bear and field vole in the last one million years (Hewitt 2000). Another effect of the ice ages is that most of expanding populations have low genetic diversity (variation) due to founder effects, i.e., a few individuals genetically contributing to the population. As individuals are forced into refugial populations, only a small portion of the population survives which can expand its range and recolonize more areas once the suitable habitat is available. For example, scientists observed that the genetic diversity of old permafrost samples of brown bears (Figure 3A) was higher than fresh samples. Individuals from ~36,000 years ago had higher genetic diversity as they were a part of a larger population.genetic diversity Around the Last Glacial Maximum (~20,000 years ago), Brown bears was then forced into small refugia, which have now expanded and current populations are derived from these small populations. Hence the genetic diversity of the current samples is lower compared to the historic samples (Leonard et al. 2000).

Interestingly, in the Southern hemisphere, many isolated island populations maybe connected during the ice ages as the sea level drops and land bridges are formed (Figure 4). The Sundaland, a major biogeographic region in South East Asia, is one the most extreme examples, where Peninsular Malaysia is connected to the islands of Sumatra, Java, Borneo along with associated islands and form a landmass twice the size of the current land area (Figure 4). These land bridges may connect many isolated populations and allow for the exchange of genetic material. For example, there were genetic exchanges between populations of Bornean and Sumatran orangutans at least till last 300,000 years ago (Natter et al. 2017) (Figure 3B). Although the Bornean orangutan is a different species fromland exposed during the Last Glacial Maximum Sumatran orangutan, there has been genetic exchange between them whenever the sea level dropped and the Sunda shelf was exposed. Further, this process of connecting and disconnecting populations also allowed for speciation and a high level of endemism we observe in Sundaland. Sundaland is one of the 25 important biodiversity hotspots and second only to the Tropical Andes in terms of the number of endemics (Myers et al. 2010). Quaternary glaciation has helped in shaping the biodiversity we observe in Sundaland. Similarly, India and Sri Lanka also got connected (Figure 4), during the glacial periods and evidence of faunal exchange have been noted in a few species (Wickramasinghe et al. 2017). However, our understanding of gene flow between India and Sri Lanka is in its infancy and more data is required to get a better understanding.

Given that the past climate has had a strong impact on shaping global biodiversity, it is imperative that we pay attention to our present climate and our contributions to global warming. In the past century, humans have had a strong impact on our planet. With the increase in atmospheric carbon dioxide emissions, we may have irreversibly changed our climate. Increase in atmospheric greenhouse gases have accelerated the global warming and current climatic models predict that we may permanently loose the Arctic ice cap in the next 20 to 30 years (Wang and Overland 2009). Arctic summers are already hotter than they were 115,000 years ago and increase warming may lead to longer unpredicted droughts, heavy flooding, stronger cyclones. Climate change has already had a strong impact on the current biodiversity. Many montane species are moving uphill as the temperatures increase and their habitats shrink. Increase in global temperatures have put enormous pressure on these populations, which extremely vulnerable to local extinctions. Similarly, increase in atmospheric carbon dioxide has led to acidification of oceans and coral bleaching (Figure 3C), wherein the corals expel the symbiotic algae from their tissue. These algae provide corals with nutrition and the loss of algae prevent future growth and leave the coral more susceptible to diseases. However, preventing the loss of biodiversity is dependent on us. With most countries agreeing to limit the increases in global temperature to less than 2 0C, we have a fighting chance to save the current biodiversity and prevent drastic effects of climate change.




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Kritika Garg