Not a Mosquito, after all!

Have you ever wondered what the deadliest animal on Earth is? If you think it could be snakes or stingray or comodo dragons, you are nowhere close and the answer might as well take you by surprise. It’s the mosquitoes, according to reports published by the World Health Organization and the Bill & Melinda Gates Foundation. In terms of the number of human lives claimed per year, mosquitoes top the list with over 0.73 million. Mosquitoes are deadly because of the public health challenges they pose – they transmit disease causing pathogens when biting us and vector diseases such as malaria, filariasis, dengue, chikungunya, yellow fever, etc. While biting, mosquitoes gain access to our blood, a rich protein source required to nourish their developing eggs and sustain metabolism. Then, does that mean only female mosquitoes bite us? Yes, male mosquitoes completely rely on plant-derived sugars such as nectar, sap, etc. for nutrition and do not require our blood. But, can all female mosquitoes potentially vector disease-causing pathogens? Interestingly, the answer is a no – just 20% of the mosquitoes account for 80% of the mosquito-borne disease transmission. The next time you are bitten by a mosquito, you might probably end up empathizing with her, as she is a soon-to-be mother.

Global Aedes distribution
Figure 1. Predicted global distribution of Aedes aegypti in 2015 (The map depicts the probability
of occurrence (from 0 blue to 1 red) at a spatial resolution of 5 km × 5 km.)
Source: Kraemer et al. elife 4 (2015): e08347

Mosquitoes, of course, do not bite only humans. For instance, mosquitoes such as the Aedes albopictus – the vector of zika, dengue and chikungunya also bite cattle, rodents and birds. Their preference for a particular host is driven primarily by their availability. For instance, in forested landscapes mosquitoes’ preferences shift from human to non-human hosts. So, how do mosquitoes find us? They use our smell, heat, and visual cues together with the carbon dioxide we exhale to identify, locate and track us down (Figure 2). This is quite fascinating because mosquitoes sense us amidst all other sensory distractions in our environment. For instance, a sock worn and left aside can emit our odors and even a cup of warm water can produce thermal cues that can potentially attract mosquitoes. However, mosquitoes do not pursue these objects because their host-sensing mechanism is far robust than we can imagine. Recent research has highlighted how their tiny brain integrates information sourced from different sensory perceptions. Smell and carbon dioxide emanating from us can travel

Mosquito host-seeking
Figure 2. Mosquitoes employ multiple sensory cues to detect human hosts
Source: Adapted from: Raji, Joshua I., and Matthew DeGennaro. “Genetic analysis of mosquito detection of humans.” Current opinion in insect science 20 (2017): 34-38.

father distances in air as odor plumes and these serve as long-range cues to identify and locate us. Upon smelling us, mosquitoes follow our odor plume along the concentration gradient and upon getting closer, they employ our thermal and visual signatures (specifically contrast) as medium and short-range cues respectively to accurately track us down. Researchers at the Rockefeller University have identified orco gene in mosquitoes that produces a protein which in turn helps build receptor molecules thereby enabling them sense varied smells. Using a series of experiments, they demonstrated how mutation in orco gene affected the ability of mosquitoes to differentiate between the smell of human hosts from other animals. Another study conducted at the University of Washington, has revealed that mosquitoes sensing carbon dioxide exhibit greater attraction towards dark, moving visual objects that resemble human hosts. Particularly, carbon dioxide exposure modulates visual centers in the mosquito brain thereby enabling them to accurately locate us. Recent research has further revealed that mosquitoes’ attraction to thermal cues is contingent on the presence of carbon dioxide. This ability to seek us, though innate to an extent, is further honed by mosquitoes early in their adult life. With every host encounter, specialized molecules in the brain that transmit information between nerve fibers (referred to as neurotransmitters) help them learn and form memory. Their ability to learn and remember does not only enable them to efficiently find us but also avert risky, life-threatening situations. When biting, mosquitoes run the risk of being killed by us. In such situations, the memory derived from past experiences modulates the olfactory centers in their brain thereby causing a shift in mosquitoes’ preference for less defensive (e.g. when sleeping) or vulnerable hosts (e.g. infants and kids). If you ever wondered why you are getting bitten more often by mosquitoes than others around you, you can be quite certain that mosquitoes like you for a reason!

Across the tropics, a few weeks into the first wet season of the year, it is common to come across newspaper headlines mentioning a dengue or chikungunya breakout. In a months’ time, the news on malaria and filaria breakout would follow. While all four are mosquito-borne diseases, why does dengue or chikungunya incidence always precede malaria or filaria? The answer lies not in the disease par se but in the mosquitoes that vector it. Dengue and chikungunya are vectored by Aedes mosquitoes while malaria and filaria are vectored by Anopheles and Culex mosquitoes respectively. The eggs laid by Aedes mosquitoes are adapted to withstand dry conditions by lying dormant and hatch subsequently upon arrival of the rain. This adaptation enables Aedes mosquitoes emerge in enormous numbers early in the wet season thereby resulting in dengue and chikungunya outbreaks well ahead of other mosquito-borne diseases. A study on climatic patterns and outbreaks of dengue, chikungunya and Zika revealed that disease outbreak coincided with peak average precipitation in South and Southeast Asia and Rio de Janeiro thereby corroborating this theory. These findings lay a strong emphasis on two aspects, both scientific and societal, pertaining to the control of vector populations and mosquito-borne diseases: 1. the need to understand links between mosquito biology, disease incidence, and climactic patterns, and 2. the need to leverage technology to raise awareness and engage public in preparing our surroundings prior to the wet season based on weather forecasts.

Effective vector control measures are the need of the hour because traditional strategies are becoming ineffective. Buildup of resistance to insecticides and larvicides such as DDT, permethrin, malathion, etc. is on the rise in mosquito populations. Exposure to sub-lethal doses of these insecticides, apart from contributing to resistance buildup also alters mosquito behavior. Mosquitoes learn to associate these repellents with the availability of a potential host for blood feeding via a phenomenon known as ‘aversive learning’. Anopheles funestus mosquitoes in sub-Saharan Africa that primarily bite hosts for blood in the night use odor cues emanating from repellents to lurk around and bite human hosts early in the morning while they are out of insecticide-treated bed nets. Such shifts in circadian activity of mosquitoes pose steep challenges in mitigation of mosquito-borne diseases. Forced application of these chemicals in higher doses to compensate for insecticide resistance has had undesirable outcomes, both on the environment and public health. Consequently, these chemicals are banned from use in most countries and the world is now inching towards development and release of genetically modified sterile male mosquitoes using gene drive. Female mosquitoes in the wild that mate with these sterile male mosquitoes lay eggs that won’t hatch. This technique is currently being implemented in Singapore on a trial basis and the results thus far are a mixed bag. Keeping mosquito populations under check requires multiple bouts of sterile male mosquito release and it is turning out be an expensive affair. Simultaneously, biological control measures involving release of fishes and dragonfly larvae that feed on larval mosquitoes are also being considered. But release of such natural predators could result in unprecedented impact on biodiversity; release of Gambusia holbrooki fish has resulted in decline of several species of fish and frogs in Australia. The scientific community is indeed excited and hopeful about eliminating mosquitoes using these novel strategies. But truly we will have to wait to see if these are good enough to counter the formidable mosquitoes.

Yes, referring to mosquitoes as a formidable species is not an overstatement. If combating mosquitoes

Mosquito pollinator
Figure 3. Mosquitoes play an important role as pollinators
Source: Pixabay license

could be considered a one-on-one duel, we humans thus far have been on the losing side. Almost every attempt targeted at controlling mosquito populations, though effective in the short-term, has failed in the long-term. If mosquitoes are so deadly, why should not a world without mosquitoes exist? Firstly, not all mosquitoes are notorious, disease-causing pests. Of the approximately 3500 named species, less than 5% of those bite humans and vector diseases. Second, mosquitoes are pollinators and are prey to several other insects; the eco-system services they provide both directly and indirectly could be crucial in sustaining biodiversity in urban settings. Both male and female mosquitoes, in pursuit of sugary nectar as a source of nutrition, end up offering pollination services for plants. While not much is known about this facet of mosquitoes, a study published this year in the Proceedings of the National Academy of Sciences has revealed the olfactory bases of orchid pollination by mosquitoes. Another study on the biodiversity of the Amazon has credited disease causing mosquitoes amongst other insects for guarding sections of the rainforests in its pristine form by deterring several multinational mining and timber logging projects. Above all, from an ethical view point, every species on Earth has its own right to live. Mosquitoes are meant to be managed and not exterminated. The easiest way to manage mosquitoes is to restrict their access to breeding sites and keeping our surroundings clean. A society that is disciplined and responsible towards the environment will not have to complain about mosquitoes or mosquito-borne diseases!

References

  1. Choo F. 2019. Sterile male mozzies released in NEA study to fight dengue, Zika”. The Straits Times. 23 February 2019 https://www.straitstimes.com/singapore/environment/sterile-male-mozzies-released-in-nea-study-to-fight-dengue-zika.
  2. DeGennaro M, McBride CS, Seeholzer L, Nakagawa T, Dennis EJ, Goldman C, Jasinskiene N, James AA, Vosshall LB. 2013. orco mutant mosquitoes lose strong preference for humans and are not repelled by volatile DEET. Nature 498(7455):487.
  3. Fuller TL, Calvet G, Estevam CG, Angelo JR, Abiodun GJ, Halai UA, De Santis B, Sequeira PC, Araujo EM, Sampaio SA, de Mendonça MC. 2017. Behavioral, climatic, and environmental risk factors for Zika and Chikungunya virus infections in Rio de Janeiro, Brazil, 2015-16. PloS one 12(11):e0188002.
  4. Lahondère C, Vinauger C, Okubo RP, Wolff G, Akbari OS, Riffell JA. 2019. The olfactory basis of orchid pollination by mosquitoes. bioRxiv: 643510.
  5. Liu MZ, Vosshall LB. 2019. General visual and contingent thermal cues interact to elicit attraction in female Aedes aegypti Current Biology 29(13):2250-2257.
  6. Pyke GH. 2008. Plague minnow or mosquito fish? A review of the biology and impacts of introduced Gambusia Annual Review of Ecology, Evolution, and Systematics 39:171-91.
  7. Servadio JL, Rosenthal SR, Carlson L, Bauer C. 2018. Climate patterns and mosquito-borne disease outbreaks in South and Southeast Asia. Journal of Infection and Public Health 11(4):566-71.
  8. Sougoufara S, Diédhiou SM, Doucouré S, Diagne N, Sembène PM, Harry M, Trape JF, Sokhna C, Ndiath MO. 2014. Biting by Anopheles funestus in broad daylight after use of long-lasting insecticidal nets: a new challenge to malaria elimination. Malaria Journal 13(1):125.
  9. Vinauger C, Lutz EK, Riffell JA. 2014. Olfactory learning and memory in the disease vector mosquito Aedes aegypti. Journal of Experimental Biology 217(13):2321-30.
  10. Vinauger C, Van Breugel F, Locke L, Tobin K, Dickinson M, Fairhall A, Akbari O, Riffell J. 2019. Visual-Olfactory Integration in the Human Disease Vector Mosquito Aedes aegypti. Current Biology https://doi.org/10.1016/j.cub.2019.06.043.
  11. Webb C, Joss J. 1997. Does predation by the fish Gambusia holbrooki (Atheriniformes: Poeciliidae) contribute to declining frog populations? Australian Zoologist 30:316-24.

 

About Author :

Karthikeyan ChandrasegaranKarthikeyan Chandrasegaran                                                 

Department of Biochemistry

Virginia Polytechnic Institute and State University

Blacksburg VA, USA

e-mail: karthikeyan@vt.edu

Living in a fool’s paradise: The anatomy of doom

Few weeks back I returned home to the whimsical December chillness of South Bengal and was immediately absorbed into anxious addas centered around the recent surge in an unpredictable weather pattern and our role in it. It seemed that many of us have finally awakened to the present and clear danger of climate change, a phenomenon which in its original form has over the course of the history of life on Earth shaped its trajectory and diversity, but in its present form threatens to obliterate a huge fraction of life forms and possibly endanger existence of the human species as well. The human civilization, specifically in the past few centuries has directed an unprecedented onslaught on its surrounding environment, forcing the most drastic pattern of climate change. As a consequence, we are experiencing the sixth mass extinction in the history of life on Earth (Dirzo et al. 2014).

As we witness our environment crumbling under the sheer pressure of the human civilization, we are yet to fathom the rate and scale of the disaster which we brought upon life-forms. Few indirect references point towards the ominous signs of the link between urban civilization and endangerment or extinction of wildlife (McKinney 2002). For example, industrialization led to warmer climate which in turn rises temperatures in the poles causing the melting of ice sheets. Inhabitants of the polar regions like the polar bear and penguins, now face alarming levels of food scarcity (Hunter et al. 2010; Jenouvrier et al. 2014). Due to lack of arctic ice, polar bears often have to cover exceedingly long distances in search of prey. Similar is the fate of penguins who face heightened mortality due to exhaustion, fast depleting prey base and lack of suitable nesting sites. Wildfires rage in Australia, Europe and North America, fanned by historically high temperatures, and resulting in mass mortality of wildlife in heat waves as well as wildfires. Closer home, weather patterns are growing erratic, rising sea levels threatens the Sundarbans and warmer temperatures aid the spread of tropical diseases, further adding more gloom to our already miserable existence (Patz et al. 2005). For humans, in a nutshell, life is becoming harder and many of us are in the danger of becoming climate refugees in the near future. The financial burden of climate change is almost insurmountable, but a spectacular lack of public awareness and political will across the globe has ensured that we remain mostly illiterate when it comes to securing the future of our generation and that our progenies. The signs are so overwhelming that we can no longer sit back and sigh over a cup of piping hot tea because there may not be a tomorrow to save.

Climate change is here and we need to act fast and act now. However, any action grows upon informed decision making. Hence in this primer, I will elaborate a little about our scientific knowledge of effect of climate change in wildlife. I will expand this column further in future to add more dimensions of climate change and reveal how our survival in completely entwined with our environment.

The earth has experienced repeated episodes of climate cooling and warming over its history of billions of years. These earth-historic events of climate change remain one of the most critical factor that has shaped the trajectory of life in this planet (see Garg 2019 for a more nuanced understanding). While fossil records were the mainstay of scientific research to understand species extinction, high-throughput contemporary technologies of genome sequencing and exhaustive bioinformatic tools have provided some excellent discoveries that not only complements fossil data but also greatly advances our knowledge in ways that we could not know by traditional methods. The Genome of an individual is like the core database and the blueprint of our biological identity. In simple terms it represents the total DNA that is stored in each cell of our body. Genome sequencing technologies aim to sequence a genome to its entirety, and the resulting data requires hundreds of Gigabytes to Terabytes of computational space and specialized computers like servers and workstations for analyses. This fast-growing set of big data when analyzed by extensive bioinformatic and statistical protocols (each analysis often runs for several months), has already returned startling information about the biotic response to past episodes of climate change. For example, we now know that endangered mammals, specifically carnivores mostly fared badly in response to earth-historic climatic fluctuations in the Pleistocene epoch (~2.58 million years ago – ~12000 years ago), specifically during the period comprising of the last documented episodes of climate warming (Last Interglacial, around 110,000 to 130,000 years ago) and climatic cooling (resulting in the Last Glacial Maxima around 18,000 years ago) (Kim et al. 2016). Schematic of population fluctuation due to earth-historic climate change in few bat species Many species of birds, specifically endangered ones reacted strongly to climate change with their populations fluctuating in response to changes in global temperature and sea level (Nadachowska-Brzyska et al. 2015). However, the most extreme examples are possibly exemplified by the fate of bats, who regardless of being commonly occurring or endangered, seems to have been profoundly affected by the historical events of climate cooling and warming (Chattopadhyay et al. 2019a) (Figure 1). A recent collaborative study led by this author observed that most study species of bats entered the present epoch of warm climate that is the Holocene (~11,650 years ago) with a historically low effective population size (Chattopadhyay et al. 2019a) (Figure 1).

Their responses to earth-historic climate change seemed to be influenced not only by available habitat but also by their biological traits like body size and capability of long flight (Chattopadhyay et al. 2019a). In simple terms, effective population size represents the number of individuals who can reproduce and contribute to the diversity of the next generation. This number serves as a proxy of the genetic diversity and represents the overall fitness of a population or species. As a rule of thumb, higher the effective population size, higher is the genetic diversity and overall health of the population, allowing for a better chance of future survival. Hence, low historical population size of bats in the recent past makes them more vulnerable to extinction possibilities under further climatic upheavals (Chattopadhyay et al. 2019a). While the number of species in these panels of investigations were miniscule compared to the vast diversity of existing wildlife, all these studies were limited by the extent of availability of Genomes from diverse species groups on public databases. As more genomes from across all major living taxa will be sequenced and made freely available on public databases in the coming decade, this will radically revolutionize our understanding of the responses of life forms to climate change.

While studying species response to earth-historic climatic fluctuations, we also realized that we can leverage this information to understand the effect of a more proximal episode of climate change that occurred in response to the industrialization during the past few centuries, specifically during the past few decades which were characterized by ultra-rapid urbanization and is now also called the human dominated era of Anthropocene (post 1945, Corlett 2015). The Anthropocene has witnessed an almost unparalleled episode of destruction of natural habitats, sudden rise in global temperature and the sixth mass extinction in the history of life (Dirzo et al. 2014). This has effectively necessitated a knee-jerk reaction from scientists and governments to understand and mitigate damages to wildlife from this calamitous disaster. Again, armed with sophisticated genomic technologies, scientists are hoping to leverage species histories to also predict species responses and their survivability going into the future. In a nut-shell, if we can reconstruct the trajectory of a species or a population going back to regimes of past climate changes, then we may ultimately predict the survivability of the species/ population under the present climatic regimes and also into the future and tailor conservation management solutions specific to each endangered population. However, the first step in this process is to accurately reconstruct species trajectories in the recent past.

While technological advancements in DNA sequencing and analytical protocols have help us understand the past, it is still difficult to reconstruct more recent histories. However, museum collections over last few centuries when compared alongside contemporary populations, provide an avenue to understand evolutionary trajectories between these different time points (Chattopadhyay et al. 2019b). Unfortunately, DNA within these museum samples are heavily degraded due to storage as well as chemical damage from preservatives. Obtaining data from these samples using traditional methods is difficult as well as expensive. Yet, recent advances in genomic technologies has made possible to generate large-scale DNA sequencing data from such samples and coupled with sophisticated bioinformatic tools, we can now generate usable data sufficient for exhaustive evolutionary analyses. For example, comparing genomic data of woolly mammoth fossils from about 45,000 years, when population size was high to a sample from 4,300 years ago revealed detrimental effects of small population size and isolation, which must have preceded their extinction from one of their last strongholds in the Wrangel Island in the arctic ocean (Rogers and Slatkin 2017).

However, until recently no study had documented in detail, the evolutionary responses of a species to the Anthropocene. In a study that is possibly one of the first of its kind, this author led a research venture addressing the effect of human-induced climate change on an urban population of a commonly occurring fruit bat (Cynopterus brachyotis) in the island population of Singapore to address this issue (Chattopadhyay et al. 2019b). We generated large tracts of genomic data from a contemporary population sampled during 2012 and compared it with museum samples collected in 1931, slightly preceding the advent of Anthropocene. Simple schematic representation of population crash in the Singaporean population of the Sunda fruit BatAfter painfully reconstructing the species history using this time-stamped data we observed signatures of drastic decline in the population size within this species in Singapore (Figure 2), coinciding with the advent of the Anthropocene that also witnessed rapid urbanization and massive loss of green cover in Singapore (Corlett 1992). When we compared the genetic diversity between these two time points, we observed large decay in diversity within the contemporary population compared to the pre-Anthropocene dataset, firmly establishing the ill-effect of human mediated habitat degradation during this period as a potential cause of endangerment.

These observations are particularly important for understanding human-induced climate change. On one hand, these results directly link the endangerment of wildlife to human urbanization, while on the other hand it calls for immediate alarm even a commonly occurring species was found to be greatly affected by human mediated habitat alterations and climate change. If a common species is so severely affected by urbanization, then the fate of endangered wildlife might be even more severe and catastrophic. Last but not the least, these fruit bats are important keystone species, performing critical role in pollination, germination and also regeneration of forest cover of the native flora and are essential for ecosystem functioning (Chattopadhyay 2018) and their decline can adversely affect in many unpredictable ways thereby affecting our survivability as well.

Unfortunately, we have just woken up to this climate emergency, and many more research studies are needed to clearly understand the extent of endangerment that Anthropocene has caused to both common species as well as endangered ones. Only then can we proceed to model future survivability of these species and design conservation management programs to save them from extinction.

 

Acknowledgment

BC thanks Dr. Kritika M Garg for helping in the manuscript preparation; and also Dr. Rajasri Ray and Dr. Avik Ray for their comments on an earlier version of the manuscript.

 

References:

  1. Chattopadhyay B. 2018. Tales of the night: Chapter I. CEiBa Newsletter 1(3):14–19. 10.13140/RG.2.2.17901.23526.
  2. Chattopadhyay B, Garg KM, Ray R, Rheindt FE. 2019a. Fluctuating fortunes: genomes and habitat reconstructions reveal global climate-mediated changes in bats’ genetic diversity. Proceedings of the Royal Society Biological Science 286:20190304.
  3. Chattopadhyay B, Garg KM, Mendenhall IH, Rheindt FE. 2019b. Historic reveals Anthropocene threat to a tropical urban fruit bat. Current Biology 29:R1299–300.
  4. Corlett RT. 1992. The ecological transformation of Singapore, 1819-1990. Journal of Biogeography 1:411–420.
  5. Corlett RT. 2015. The Anthropocene concept in ecology and conservation. Trends in Ecology and Evolution 30:36–41.
  6. Dirzo R, Young HS, Galetti M, Ceballos G, Isaac NJ, Collen B. 2014. Defaunation in the Anthropocene. Science 345:401–406.
  7. Garg KM. 2019. Last Ice Age: understanding Earth’s climatic history. CEiBa Newsletter 2(1):11–14. 10.13140/RG.2.2.11159.42409.
  8. Hunter CM, Caswell H, Runge MC, Regehr EV, Amstrup SC, Stirling I. 2010. Climate change threatens polar bear populations: a stochastic demographic analysis. Ecology 91:2883–2897.
  9. Jenouvrier S, Holland M, Stroeve J, Serreze M, Barbraud C, Weimerskirch H, Caswell H. 2014. Projected continent-wide declines of the emperor penguin under climate change. Nature Climate Change 4:715.
  10. Kim S, Cho YS, Kim HM, Chung O, Kim H, Jho S, Seomun H, Kim J, Bang WY, Kim C, An J. 2016. Comparison of carnivore, omnivore, and herbivore mammalian genomes with a new leopard assembly. Genome Biology 17:211.
  11. McKinney ML. 2002. Urbanization, Biodiversity, and Conservation: The impacts of urbanization on native species are poorly studied, but educating a highly urbanized human population about these impacts can greatly improve species conservation in all ecosystems. Bioscience 52:883–890.
  12. Nadachowska-Brzyska K, Li C, Smeds L, Zhang G, Ellegren H. 2015. Temporal dynamics of avian populations during Pleistocene revealed by whole-genome sequences. Current Biology 25:1375–1380.
  13. Patz JA, Campbell-Lendrum D, Holloway T, Foley JA. 2005. Impact of regional climate change on human health. Nature 438:310.
  14. Rogers RL, Slatkin M. 2017. Excess of genomic defects in a woolly mammoth on Wrangel island. PLoS Genetics 13:e1006601.

About Author :

Balaji Chattopadhyay

e-mail: balaji.chattopadhyay@gmail.com

WILD UNCULTIVATED EDIBLE PLANTS OF INDIA

Part 4

(……after part 3)

Bauhinia vahlii Wight & Arn. 

Family: Leguminaceae

This plant is a crawling member of the upright and prodigious Gulmohar family and ranks as one of the largest creepers in India – is also known as ‘maloo creeper’. This creeper is found across the country and considered as an enemy of its refuge trees. The strong and woody stem can grow into a huge creepy giant, reaching up to 30 m long and 20 cm thick. Other than its ornamental value, the tree is well utilized throughout India for its edible part, i.e., seeds. Traditionally, the seeds are roasted and eaten or often used as a pulse substitute. It is well-embraced in dietary use among the tribals across India from Gujarat to Manipur, Uttarakhand to Andhra Pradesh including central and east Indian states. In addition to the seeds, the flower bud and stem bark have some food value and relished in Bihar and Gujarat. Also, tender young pods and leaves are used as vegetables. Research shows that seeds power-packed with lipids, essential amino acids (isoleucine, valine, histidine, leucine, phenylalanine, lysine and tyrosine) and minerals (nitrogen, calcium, iron, magnesium). Perhaps, this gigantic creeper has not reached common households owing to limited efforts towards domestication and cultivation.  Bauhinia vahlii Wight & Arn

 

Juglans regia L.

Family: Juglandaceae

Although commonly known as English walnut or Persian walnut the plant is widely distributed in the Himalayan states of India. Walnut kernels are very popular as dry fruit across India and abroad alike. The nut is culturally well-embedded in the dietary habit of the hill communities of Uttarakhand, Himachal Pradesh, West Bengal, Assam, and Manipur. The kernels are rich in omega-6 and omega-3 polyunsaturated fatty acids (PUFA). Besides, phytosterols, which help in lowering total plasma cholesterol and low density lipoprotein, are also present. Studies also unearthed the presence of many essential minerals (calcium, iron, magnesium, sodium), vitamins (A, C, E and K), and proteins. Walnut is classified as an important species for human nutrition owing to high protein and oil contents and made its entry into the FAO list of priority plants. Though the traditional recipes of walnut are yet to seep into the Indian kitchens, several attempted the use of walnuts in laddus (the nut is mixed with dates and other dry fruits and made into balls with ghee), but short shelf life of the delicacies remained a major problem. The use of the nuts in place of other popular nuts like peanut or cashew is not yet explored perhaps due to limited production. But the nuts are trending well in online stores and supermarkets as the culture of consumption of raw and processed nuts shooting up rapidly. Juglans regia L.

 

Leucas aspera (Willd.) Link

 Family: Lamiaceae

This herbaceous plant is very common, grows rampantly in open-spaces showing off its tiny white flowers, and considered as a ‘weed’ in many parts of the country. It is herbaceous and grows up to 15-60 cm with linear leaves and white flowers. It is colloquially called as drone pushpam, gophaa, chhota halkusa, thumba, ghal ghase or thunni in different cultural geographic regions. In the south of India especially in the states of Tamil Nadu, Andhra, and Kerala, the leaves and flowers are made into a paste with tamarind, lentils, and red chilies to accompany sumptuous dosas and idlis. The flowers are used to make ‘ada’ – a delicious south Indian version of crepe or pancake. Some modern culinary specialists advocate the use of the decoction of the leaves with ginger in the form of gravy due to the anti-oxidative properties of the plant. Like southern part, the plant is also very popular among peoples of the north and north-east states of India. Leaves and shoots are used as vegetables either boiled or consumed with spices among different tribes. Nutritional evaluation revealed the plant is loaded with multiple key vitamins (ascorbic acid, riboflavin, thiamin, niacin and beta-carotene), minerals (calcium, potassium, magnesium and phosphorous) and micronutrients (manganese, zinc and iron).Leucas aspera (Willd.) Link

Opuntia dilleni (Ker Gawl.) Haw.

 Family: Cactaceae

The plant is different from the common prickly pear (Opuntia indica), bears strikingly bright yellow flower and can be found along the coastal regions and beyond. Owing to its resemblance with serpent head, it is called as naga phana, but also known as sappathi kalli, chorhathalo, etc. The plant bears alluring red fruit conspicuously seated on the modified stem (cladode), the fruit is a popular item among tribals of Tamil Nadu, Andhra Pradesh, Karnataka as well as in Bihar. Studies say that the juice of the cactus plant possesses many curative, i.e., anti-allergic, anti-oxidative and anti-carcinogenic properties. The young tender shoots (cladodes) is fortified with high amount of macro minerals like, potassium, sodium, magnesium, calcium and phosphorous along with important micro minerals (e.g., iron, zinc, copper, manganese). Fruits too have high nutritional value as they are rich in vitamin C, E and beta carotene, protein, fats, minerals (potassium, magnesium, calcium, phosphorous) and amino acids (proline, taurine and serine). Nutritional beverages from the plant (along with papaya and mango) shows promising anti-oxidant activities and act as a potential energy booster. Initiatives for traditional food preparation using the fruit have been gathering pace (e.g., jam, juice, nectar, juice concentrate, and syrup). Although the cultivation and processing of the plant have already gained popularity, a large majority is unaware of the nutritional benefits of the plant thus left under-utilized.Opuntia dilleni (Ker Gawl.) Haw.

Glimpses Of Nature And Culture

Honeytrap by Rhododendrons

In 67 B.C.E, at Trabzon near Black Sea famous general, Gnaeus Pompeius Magnus (Pompey the Great) and his Roman army faced an unprecedented situation. While chasing the Persian army of King Mithridates of Pontus, they were exposed to full pots of local honey, undoubtedly lucrative drink forHoneytrap by Rhododendrons exhausting soldiers. The result was devastating after a happy sip to that special honey, a literal “honeytrap”. The soldiers were disoriented, unable to stand on their feet and the very next day it was a cakewalk for hidden Persian army to massacre nearly 1000 soldiers who were still in that unstable condition. The warfare history repeated at A.D. 946, when 5000 Russian soldiers were killed under the same “honeytrap” by the followers of Olga of Kiev and in 1489, 10,000 Tatar soldiers had the same fate planned by the Russians at the same region. However, these ghastly experiences and other small scale incidences did not create much impact on the popularity of this honey aka. “Mad honey”, “Poison honey”. Considered as one of the costliest honey in the world ($129.95/kg www.miel-fou.com), it has medicinal and hallucinogenic properties owes to the presence of Grayanotoxin. The source plants mostly belong to the Ericaceae family i.e. our Rhododendrons, Azaleas with their dazzling bright coloured flowers. Very well-known examples are Rhododendron ponticumRhododendron maximumRhododendron flavum, Azaleas in the Black Sea and Caucasus region. Similarly, Mad honey incidences are not restricted in the Black Sea region, these nerve intoxicating properties have been reported from Asia Minor, southern Russia, The Himalayas (Nepal), eastern United States and Pacific north-west. In the Himalaya, Apis dorsata laboriosa the largest honeybee of the world produces red honey from Rhododendron species at the higher altitude region which is also famous for its intoxicating property. However, dosage standardisation and awareness on its excess consumption subdue the mortality rate in recent time thus skyrocketing its popularity. Next time, don’t allow the honey to decide your destination either “hallucinogenic heaven” or “monstrous hell”.

Source: Adrienne Mayor (1995). Mad Honey. Archaeology, pp. 32-40

Image: A) Rhododendron ponticum (Source: Eiffel/Google Image)

B) Honey hunters in Nepal. (Source: https://www.theguardian.com/travel/gallery/2014/feb/27/honey-hunters-nepal-in-pictures#img-4

 Collector: Rajasri Ray

 

Snacks from the coastguard

 Mangroves are natural coast guard for many regions with their characteristic root system, ability toSnacks from the Mangroves grow in salt-rich soil and are with a bagful of ecosystem services. Mangroves are well-known food resources for many but less known for humans. In southeast Asian countries of Indonesia and Thailand, foods prepared from mangrove spp. are considered as a local delicacy in the coastal region. The serrated leaves of Holy mangrove (Acanthus ilicifolius), fruits of Mangrove apple (Sonneratia caseolaris), Orange mangrove (Bruguiera gymnorrhiza), Nypa palm (Nypa fruticans) and few others are ingredients for mouthwatering snacks like cake, cookies, juice, syrup, and jam. They are high in carbohydrates, vitamins, fat and fibre contents, therefore a good alternative for mainstream market-friendly foods too. What are you waiting for? Next time, your trip to the Malay Archipelago must be accompanied by “Coastguard food”.

Source: Situmorang R.O.P and Barus S.P. (2015). Mangrove management as source of food

alternative by the women fishermen group in Sei Nagalawan, North Sumatra, Indonesia. Paper A 14. The International Conference of Indonesia Forestry Researchers III, Bogor, Indonesia. October 21-22.

Image: Acanthus ilicifolius (Swagat2010/efloraofindia), Sonneratia caseolaris (Asokan Mash /www.flowersofindia.net), Bruguiera gymnorrhiza (Navendu Page/HerbariumJCB), Nypa fruticans (By Qaalvin – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=19416883)

Collector: Rajasri Ray

 

A taste of saffron from Tuscany – full of twists and turns

It is a story of the revival of the culture of growing a forgotten crop once quite commonly cultivated in a region. It all commenced with a yellow tinge in the ancient tubs of an old and abandoned Roman building!

The story began to unfold at an estate in Campagnatico, Tuscany of Italy when a yellow color was discovered by a localite in the Roman ruin and eventually equated with saffron. These estates were quite ubiquitous in rural Italy and of a kind preferred by urbanites to flee from bustling cities. In one such nest of someone Mr. X, he stumbled upon a dilapidated Roman ruin poignant with history. TheA taste of saffron from Tuscany color detected, words spread and reached the protagonist of our story, Ms. Anna. She was an accountant from Grosseto – a small town near the Tyrrhenian Sea. She bought a small piece of land in the area and intended to cultivate after her retirement; then she heard of this, and as the event goes by, it kindled her interest. She enquired and was told that the kind of color can only be obtained from saffron. A brief chat with local elders confirmed that once saffron was grown in Tuscany but the culture has now has become a craft of bygone era. Anna was reluctant to leave her hope and stay in despair, and so jumped to rejuvenate the lost-craft of saffron cultivation on her own. According to her, it went like this:

The whole process is full of delicate handling of the flowers that bloom for two weeks and must be picked up early morning before opening up. The tender ones after collecting in baskets, the prodigal red pistils to be picked up using hands and dry them.

The whole journey was quite tiresome given the very prolonged and laborious process of cultivation, harvesting, and extraction, but her perseverance and dedication were paid off. She was happy with her golden harvest, at last, it followed many things after her success story. She took initiative to sensitize local farmers, put her effort to hold a conference to teach people and formation of co-operatives, drawing on local governance, creating the market, etc. It turned out that the place was ideal for saffron cultivation and was once sprawling farmland famed for the crop. Tuscan and Umbrian Slow Food movement provided them with additional inertia to take it further.

So, Ms. Anna reinvented the lost tradition and mobilized local farmers which became a standard textbook example.

Now, what does the story of Anna convey? Yes, a lot of things, saffron, Tuscany, lost art, the place of food, etc. But it also tells that the food in the twenty-first century is a globalized item mixed not only with human movement and trade, also with palatability, lost in the mist and rediscovery, resurrection and market creation, governance and community initiative.

Source: Roberta Sonnino (2013) Local foodscapes: place and power in the agri-food system, Acta Agriculturae Scandinavica, Section B — Soil & Plant Science, 63:sup1, 2-7

Image: Safa.daneshvar – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=31281822; Hubertl – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=38618139

Collector: Avik Ray

 

An eel or a snake – forget it – it is a tasty fish

Gangetic mud eel or Monopterus cuchia or more commonly Cuchia is a tropical fish species widely distributed across the southern and southeastern parts of Asia. Largely owing to the elongated, slimy and compressed body, greenish or chest-nut brown body color and slithering movement, it looks more like an eel or a snake. Unfortunately, it is neither an eel and a snake, but it belongs to the family synbranchidae of the order synbranchiformes, which means although these creatures may resemble eels or their brothers, they are not related to true eels; and understandably far-placed animal very distant from the snakes.

They inhabit freshwater and brackish water and found in shallow, well-vegetated water and mud.Monopterus cuchia Mucky mud holes in shallow beels, ponds, and boro paddy fields are their favorite hang-out places. They can live in holes without water with the help of respiratory organs. They pass the entire summer in holes but sometimes coming out from the hole to take oxygen. While in the hole, they keep mouth position in a straight upper position and soon slides back completely with the slightest citing of any enemy. Unlike them, his many close relatives prefer spending their lifetime hiding in caves. The mud eel is a carnivorous and nocturnal prefers animal-based food like small fishes, mollusks, prawns, aquatic insects, small frogs, and worms, etc. Observation by onlookers say they sometimes crawl through the field and rice field bunds to the nearby locality in search of food at night, their mucky trail can be discerned by experienced eyes.

As a food, this fish is very tasty, nutritionally rich with medicinal value and is appreciated throughout its distributional range. Although it has quite a large economic demand and plays a unique role in socio-economic welfare, the populations of this freshwater eel are declining at an alarming rate from the natural water bodies due to overfishing, deterioration of water quality attributed to heavy use of agrochemicals in the rice field, and the loss of habitat.

Apart from the generic nets and traps, rural people of Bengal have a very unique way of catching this fish with frogs as bait held near the hole. A sound created in the water attracts Cuchia to grab its prey and it has to be lifted out from the hole in a single shot after it is trapped. However, it is one of the many indigenous techniques and gears people used to catch Cuchia. Mostly inspired by natural history and applying the insights from traditional knowledge, diverse tools and methods have been employed, e.g., wounding by spears, knives or sickles, stupefying fish by ichthyotoxic plants, using bamboo traps, hooks, and light fishing. The rich repertoire of human technology is a demonstration of indigenous means of natural resource management that assimilates the information from natural history, the wisdom of hunting and gathering tools and its local resources base; and most importantly, it underscores human ingenuity

 Source: S.M.Galib, bdfish.org

Collector: Avik Ray