Daniela Vergara

Postdoctoral Fellow, University of Colorado, Boulder, CO, U.S.A.


We end the year with the plant genus Cannabis, belonging to the family Cannabaceae, which also includes hops (Humulus sp.) and Hackberries (Celtis). Cannabis is most famous today for its use as a recreational drug, aka marijuana, although the legalization of this plant as a drug has been quite controversial in the United States and across the world. Despite its notoriety, however, the origins, chemical properties, reproductive strategies and dispersal of Cannabis across the globe are quite fascinating and this plant genus has been impacting human culture for ages. Cannabis is one of the oldest domesticated plants and various ancient human cultures have used it for spiritual rituals, medicinal purposes, and fiber for rope or clothing that has been extracted from hemp plants (Li 1973, 1974; Russo, 2007, 2008). The genus most likely originated in Central, South or Eastern Asia but the exact origin of Cannabis is difficult to determine because of shifts in its distribution between glacial cycles (Clarke & Merlin 2013). Humans brought this species to Europe and later to Africa and the Americas where it was cultivated and domesticated into different varieties (Clarke & Merlin 2013). 

Carolus Linnaeus, the founder of the binomial species system, was the first person to classify the Cannabis genus in 1753, and only identified a single species, Cannabis sativa L. However, Jean Baptiste Lamarck (yes, the one who came up with a first theory of adaptation, now known and disregarded as “Lamarckian evolution”) described a second species, Cannabis indica, in 1785 (Watts, 2006). While the validity of the second species is debated, the groupings “sativa” and “indica” are still commonly used. Interestingly, Cannabis has an unusual amount of genetic diversity when compared to other plant groups (Sawler et al. 2015; Lynch et al. 2016; Vergara et al. 2016). Recent scientific research has found that there are genetic clusters, and thus it is possible that several other species will be described. However, these do not seem to reflect Lamarck’s classification of C. sativa and C. indica (Sawler et al. 2015; Lynch et al. 2016; Vergara et al. 2016). 

What molecular properties and processes make this plant so popular as a recreational drug? Cannabis produces cannabinoids, which interact with our own endocannabinoid system within the brain and nervous system (Gertsch 2008). The endocannabinoid system is involved in regulating multiple physiological processes, including sleep and hunger. One of the primary and most widely known cannabinoids produced by the Cannabis plant is Δ-9-tetrahydrocannabinolic acid (THCA), which is converted to the neutral form Δ-9-tetrahydrocannabinol (THC) once heated. This neutral form interacts with the endocannabinoid system producing a psychoactive effect (gets us “high”). THC also seems to have important medical uses potentially serving as treatment for Parkinson’s disease (Carrol et al. 2012), dementia (Walther et al. 2006), and autoimmune disorders (Lyman et al. 1989). The other well-known cannabinoid in Cannabis is cannabidiolic acid (CBDA), which produces cannabidiol (CBD) when heated. Data suggest CBD, which is not psychoactive, may mitigate some of the negative effects of THC (such as anxiety and paranoia) and has potential uses in treating cancer (Soliman et al. 2015) and epilepsy (Mechoulam et al. 2002; Devinsky et al. 2014). Besides THC and CBD, Cannabis produces around 74 different cannabinoids (ElSohly et al. 2005; Radwan et al. 2008; ), which are present at varying potencies and ratios across particular cultivars and may also have medical importance, including cannabigerol (CBG) Borelli et al., 2014), cannabichrome (CBC) (Izzo et al. 2012) and Δ-9-tetrahydocannabivarin (THCV) (McPartland et al. 2015).

Cannabis also has interesting reproductive strategies. It can be either dioecious, meaning that there are male and female plants, similar to what we see in humans and other animals (Soltis et al. 2005; Bell et al. 2015). However some Cannabis varieties are monoecious, and thus produce both males and female flowers in the same plant. To make this even more confusing, when environmentally stressed, some male plants can produce female flowers and some female plants can produce male flowers. Additionally, sex is determined by two chromosomes, X and Y (thus males are XY and females are XX), but the hermaphrodites have undifferentiated chromosomes (Hirata 1929; Yamado 1943; Sakomoto et al. 1998). Interestingly, males, females and hermaphrodites can cross with each other and produce fertile offspring.

About the Author

Dr. Daniela Vergara is post-doctoral researcher at the University of Colorado, Boulder, where she is working in Dr. Nolan Kane’s lab Cannabis Genomic Research Initiative. Specifically, Daniela has been exploring the cannabinoid genes in the genome and understanding the how these genes relate to the chemotypes. Daniela also founded and is the director of a non-profit organization The Agricultural Genomics Foundation that holds a 501(C)(3) status (AGF; and aims in becoming a genomic repository (“library of genomes”) helping CGRI perform their research. AGF also educates the public about science, Cannabis, evolutionary biology, and genomics, through public talks.


Bell, C. D., D. E. Soltis & P. S. Soltis. 2010. The age and diversification of the angiosperms re-revisited. American Journal of Botany 97: 1296–1303.

Borrelli, F., E. Pagano, B. Romano, S. Panzera, F. Maiello, D. Coppola, L. De Petrocellis, L. Buono, P. Orlando & A. A. Izzo. 2014. Colon carcinogenesis is inhibited by the TRPM8 antagonist cannabigerol, a Cannabis-derived non-psychotropic cannabinoid. Carcinogenesis 35: bgu205.

Carroll, C. B., M‐L. Zeissler, C. O. Hanemann & J. P. Zajicek. 2012. Δ9‐tetrahydrocannabinol (Δ9‐THC) exerts a direct neuroprotective effect in a human cell culture model of Parkinson's disease. Neuropathology and Applied Neurobiology 38: 535–547.

Clarke, R. C. & M. D. Merlin. 2013. Cannabis: evolution and ethnobotany. University of California Press.

Devinsky, O., M. R. Cilio, H. Cross, J. Fernandez‐Ruiz, J. French, C. Hill, R. Katz, V. Di Marzo, D. Jutras‐Aswad, W. G. Notcutt & J. Martinez‐Orgado. 2014. Cannabidiol: pharmacology and potential therapeutic role in epilepsy and other neuropsychiatric disorders. Epilepsia 55: 791–802.

ElSohly, M.A. & D. Slade. 2005. Chemical constituents of marijuana: the complex mixture of natural cannabinoids. Life sciences 78: 539–548.

Gertsch, J., M. Leonti, S. Raduner, I. Racz, J.-Z. Chen, X.-Q. Xie, K.-H. Altmann, M. Karsak & A. Zimmer. 2008. Beta-caryophyllene is a dietary cannabinoid. Proceedings of the National Academy of Sciences 105: 9099–9104.

Hirata, K. 1929: Cytological basis of the sex determination in Cannabis sativa. Idengaku Zasshi. 4: 198–201.

Izzo, A. A., R. Capasso, G. Aviello, F. Borrelli, B. Romano, F. Piscitelli, L. Gallo, F. Capasso, P. Orlando & V. Di Marzo. 2012. Inhibitory effect of cannabichromene, a major non‐psychotropic cannabinoid extracted from Cannabis sativa, on inflammation‐induced hypermotility in mice. British journal of Pharmacology 166: 1444–1460.

Li, H. L. 1973. An archaeological and historical account of cannabis in China. Economic Botany 28: 437–448.

Li, H. L. 1974. Origin and use of Cannabis in Eastern Asia; Linguistic-cultural implications. Economic Botany 28: 293–301.

Lyman, W. D., J. R. Sonett, C. F. Brosnan, R. Elkin & M. B. Bornstein. 1989. Δ 9-tetrahydrocannabinol: a novel treatment for experimental autoimmune encephalomyelitis. Journal of neuroimmunology 23: 73–81.

Lynch, R. C., D. Vergara, S. Tittes, K. White, C. J. Schwartz, M. J. Gibbs, T. C. Ruthenburg, K. deCesare, D. P. Land & N. C. Kane. 2016. Genomic and Chemical Diversity in Cannabis. Critical Reviews in Plant Sciences 35: 349–363.

McPartland, J. M., M. Duncan, V. Di Marzo & R. G. Pertwee. 2015. Are cannabidiol and Δ9‐tetrahydrocannabivarin negative modulators of the endocannabinoid system? A systematic review. British journal of pharmacology 172: 737–753.

Mechoulam, R., L.A. Parker & R. Gallily. 2002. Cannabidiol: an overview of some pharmacological aspects. The Journal of Clinical Pharmacology 42: 11S-19S.

Radwan, M. M., S. A. Ross, D. Slade, S. A. Ahmed, F. Zulfiqar & M. A. ElSohly. 2008. Isolation and characterization of new Cannabis constituents from a high potency variety. Planta medica 74: 267–272.

Russo, E. B. 2007. History of Cannabis and its preparations in saga, science, and sobriquet. Chemistry & Biodiversity 4: 1614–1648.

Russo, E. B., H. E. Jiang, X. Li, A. Sutton, A. Carboni, F. Del Bianco, G. Mandolino, D. J. Potter, Y. X. Zhao, S. Bera & Y. B. Zhang. 2008. Phytochemical and genetic analyses of ancient cannabis from Central Asia. Journal of Experimental Botany 59: 4171–4182.

Sakamoto, K., Y. Akiyama, K. Fukui, H. Kamada & S. Satoh 1998. Characterization; Genome Sizes and Morphology of Sex Chromosomes in Hemp (Cannabis sativa L.). Cytologia 63: 459–464.

Sawler, J., J. M. Stout, K. M. Gardner, D. Hudson, J. Vidmar, L. Butler, J. E. Page & S. Myles. 2015. The Genetic Structure of Marijuana and Hemp. PloS One 10: e0133292.

Solinas, M., V. Cinquina & D. Parolaro. 2015. Cannabidiol and Cancer—An Overview of the Preclinical Data. In Molecular Considerations and Evolving Surgical Management Issues in the Treatment of Patients with a Brain Tumor. InTech.

Soltis, D. E., P. S. Soltis, P. K. Endress & M. W. Chase. 2005. Phylogeny and evolution of angiosperms. Sinauer Associates Incorporated.

Walther, S., R. Mahlberg, U. Eichmann & D. Kunz. 2006. Delta-9-tetrahydrocannabinol for nighttime agitation in severe dementia. Psychopharmacology 185: 524–528.

Watts, G. 2006. Science commentary: Cannabis confusions. BMJ: British Medical Journal 332: 175.

Vergara, D., H. Baker, K. Clancy, K. G. Keepers, J. P. Mendieta, C. S. Pauli, S. B. Tittes, K. H. White & N. C. Kane. 2016. Genetic and Genomic Tools for Cannabis sativa. Critical Reviews in Plant Sciences 35: 364–377.

Yamada, I. 1943. The sex chromosome of Cannabis sativa L. Seiken Ziho2: 64–68.


Jonathan Foox

Postdoctoral Associate, Institute for Computational Biomedicine, Weill Cornell Medicine, New York, New York


This month's featured taxon is Myxozoa: a bizarre, poorly understood group of microscopic, obligate parasites. Members of this taxon are typically found parasitizing teleost fish and annelid worms, though they have been observed in a wide spectrum of hosts including amphibians, birds, bryozoans, cephalopods, reptiles, shrews, and waterfowl. These parasites are globally distributed in marine and freshwater aquatic environments (though some are exclusively terrestrial), and have been found in nearly all tissue and organ types. Myxozoa is an extremely diverse group not only in distribution but in species richness, comprising over 2,200 described species distributed among over 60 genera (Lom and Dyková, 2006) – which likely represents a small fraction of the total diversity, with some estimates of 16,000 species in the Neotropics alone (Naldonia et al., 2011).

Although most myxozoan infections are innocuous, some species are well known pathogens that cause fatal diseases that can have significant economic impact, particularly on fish farms (Kent et al., 2001). One especially nasty example is Tetracapsuloides bryosalmonae, the causative agent of Proliferative Kidney Disease, which can wipe out 90% of infected salmonid populations, and even caused authorities to shut down a 183-mile stretch of Yellowstone River last summer (Young, 2016).

Each individual myxozoan has a fantastically complex life cycle that involves radical physiological transformations. Upon penetration of a host, an individual amoeboid-like reproductive body will undergo complex rounds of cellular fusion and division, before ultimately producing a reproductive spore that will eventually emerge from its host into the water column in search of its next host. These spores exhibit a stunningly diverse array of morphologies, including spherical, fusiform, pyriform, floral, round, ovoid, flattened, elongated, with or without caudal appendages, and all variations exhibit a wide variety of variation in orientation and number of constituent parts. The image gives just a taste of the incredibly morphological diversity of this taxon. In rather dramatic fashion, these spores harbor a complex organelle known as a polar capsule, which contains a coiled up filament that, upon stimulation, will rapidly evert from the capsule like the finger of a glove. The sticky filament flies through the water and latches onto the integument of the target animal like a grappling hook, allowing the spore to wriggle its way into its next host and beginning the parasitic cycle anew.

But perhaps the most impressive thing about Myxozoa is its position within the tree of life. These microscopic, morphologically simplistic parasites are members of the phylum Cnidaria, the lineage containing animals such as jellyfish, sea anemones, and corals. Indeed, myxozoans are extremely divergent, incredibly reduced, highly derived evolutionary cousins of these commonly known creatures. And this relationship of myxozoans to its cnidarian allies renders the group one of the most dramatically degenerate parasitic radiations known to biology. Myxozoans have neither tentacles, nor gastrovascular cavities, nor even tissue layers – and yet, they are cnidarians, by virtue of their polar capsules, which are homologous to cnidocytes (the stinging organelles only found within Cnidaria).

To put it into perspective: the size difference between an individual myxozoan spore and the common moon jelly is equivalent to the size difference between a human and Mt. Everest. Quite the difference.

And yet, this evolutionary relationship was not understood for nearly two hundred years. After first discovery in the early 19th century, myxozoans were categorized as various protistan lineages. Upon their confirmation as cnidarians not much more than 20 years ago (Siddall et al., 1995), biologists realized that myxozoans are not only incredibly derived cnidarians, but that they are the smallest and perhaps simplest animals in existence. Having lost nearly all diagnostic features known to animals (cellular structures such as centrioles and cilia), myxozoans stretch the very limit of what we understand to be "animals". It is only fitting that we save for the end of the year a taxon that stretches the limits of our biological imagination.


Kent, M.L., K.B. Andree, J.L. Bartholomew, M. El-Matbouli, S.S. Desser, R.H. Devlin, S.W. Feist, P.P. Hedrick, R.W. Hoffmann, J. Khattra, S.L. Hallett, R.J.G. Lester, M. Longshaw, O. Palenzeula, M.E. Siddall ME & C.X. Xiao. 2001. Recent advances in our knowledge of the Myxozoa. J Eukaryot Microbiol  48: 395–413.

Lom, J., & I. Dykova. 2006. Myxozoan genera: definition and notes on taxonomy, life-cycle terminology and pathogenic species. Folia Parasitology 53: 1-36. London, pp. 115–154.

Naldonia, J., S. Aranab, A.A.M. Maiac, M.R.M. Silvac, M.M. Carrieroc, P.S. Ceccarellid, L.E.R. Tavarese & E.A. Adrianof. 2011. Host–parasite–environment relationship, morphology and molecular analyses of Henneguya eirasi n. sp. parasite of two wild Pseudoplatystoma spp. in Pantanal Wetland, Brazil. Veterinary Parasitology 177: 247–255.

Siddall, M.E., D.S. Martin, D. Bridge, S.S. Desser & D.K. Cone. 1995. The demise of a phylum of protists: phylogeny of Myxozoa and other parasitic Cnidaria. Journal of Parasitology 81: 961–967.

Young, Ed.  2016.  A Tiny Jellyfish Relative Just Shut Down Yellowstone River.  The Atlantic: .


Ricardo Bressan Pacifico

Ph.D. Student, Plant systematics and biogeography lab - Maringá State University, Maringá, Brazil

Photo credit. A. V. Scatinga.

Photo credit. A. V. Scatinga.

With Halloween just around the corner, our taxon of the month is a recently described and unique genus of plants with unusual feeding habits, Philcoxia. This genus was first described 17 years ago, known only from three species (Taylor & Souza, 2000), although since then several additional species were recently discovered bringing the number of species in the genus to seven (Scatigna et al., 2015; 2017). All Philcoxia species are rare and are endemic to central Brazilian mountaintop grasslands, usually known as campo rupestre (Taylor & Souza, 2000). They are annual herbs, usually less than 30 cm tall, with delicate roots and stems, and small white to purple flowers measuring less than 1 cm in length. However, the most striking features of Philcoxia took more than a decade to be discovered. All species have underground leaves to which many nematodes attach and these leaves look somewhat similar to those found in carnivorous plants, a feature which caught the attention of researchers from California and Brazil, who decided to perform carnivory tests (Fritsch et al., 2007). The initial carnivory test results were negative (Fritsch et al., 2007), however, a few years later, a new and creative experiment shed light on this matter. In this experiment, radioactive nitrogen (15N) was used to feed bacteria (Escherichia coli) that were fed to to a population of nematodes (Caenorhabdtis elegans), which, in turn, were placed over the underground leaves of Philcoxia minensis for two days. The idea was to track the nutrient acquisition of Philcoxia, i. e., to see if the radioative nitrogen from nematodes would somehow be absorbed by this plant. The fast absorption of the 15N revealed by the elevated concentration of it in Philcoxia leaves strongly suggested that the nematodes were digested (instead of naturally decomposed) and absorbed by Philcoxia leaves (Pereira et al. 2012)⁠ suggesting that this genus of plants is carnivorous and feeds on nematodes. Carnivory evolved at least six times within angiosperms (flowering plants) and about 20 carnivorous genera distributed in 10 distinct families have been identified. A general cost–benefit model predicts that carnivory will be restricted to well lit, low-nutrient areas, where the major source of important nutrients such as nitrogen and phosphorus will be obtained from captured and digested invertebrates (Pereira et al. 2012).⁠ Philcoxia, like other carnivorous plants, live in nutrient-poor soils and are the only known carnivorous plants in the Plantaginaceae family (Pereira et al. 2012). The unusual new mechanism of carnivory discovered in Philcoxia caught public attention in high impact scientific journals such as Nature (Rowland, 2012).


Fritsch, P. W., F. Almeda, A. B. Martins, B. C. Cruz and D. Estes. 2007. Rediscovery and phylogenetic placement of Philcoxia minensis (Plantaginaceae), with a test of carnivory. Proceedings of the California Academy of Sciences 58: 447–467

Pereira, C. G., D. P. Almenara, C. E. Winter, P. W. Fritsch, H. Lambers and R. S. Oliveira. 2012. Underground leaves of Philcoxia trap and digest nematodes. Proc. Natl. Acad. Sci. U. S. A. 109: 1–5. doi:10.1073/pnas.1114199109.

Rowland, K. 2012. Hungry plant traps worms underground. Nature (news). doi:10.1038/nature.2012.9757

Scatigna, A. V., V. C. Souza, C. G. Pereira, M. A. Sartori, and A. O. Simoes. 2015. Philcoxia rhizomatosa (Gratioleae, Plantaginaceae): A new carnivorous species from Minas Gerais, Brazil. Phytotaxa 226: 275–280

Scatigna, A. V., Silva, N. G., Alves, R. J. V., Souza, V. C. and O. Simões. 2017. Two New Species of the Carnivorous Genus Philcoxia (Plantaginaceae) from the Brazilian Cerrado. Systematic Botany 42:351-357. doi: 10.1600/036364417X695574

Taylor, P., Souza, V. C., Giulietti, A. M. and R. M. Harley. 2000. Philcoxia: A new genus of Scrophulariaceae with three new species from eastern Brazil. Kew Bulletin 55: 155–163. 


Stephanie F. Loria

We have been pretty biased towards multicellular organisms in the Taxon of the Month posts. But this month, we are doing justice to our single-celled organism friends giving them the recognition they deserve as they are so crucial to the health of all multicellular life. For September, we focus our attention on the bacteria family, Enterobacteriaceae. Enterobacteriaceae are quite diverse and include more than 200 species in 51 genera (Octavia & Lan 2014; Janda & Abbott 2015). All Enterobacteriaceae are gram-negative, meaning that they possess a thin peptidoglycan layer in their cell walls causing them to appear pink after Gram staining (Beveridge 2001). Some well-known Enterobacteriaceae members include the medically important Escherichia coli, Salmonella and Klebsiella (Janda & Abbott 2015). E. coli is an essential human gut bacterium that can also act as a pathogen under certain conditions (Janda & Abbott 2015). Salmonella is notorious for causing illness of the human digestive system, which is sometimes fatal, and is transmitted through food and water contaminated with feces (Janda & Abbott 2015). Klebsiella species are found free-living in soil or water or in vertebrate digestive systems but are also responsible for a number of human illnesses including urinary tract infections and pneumonia.

Bacteria from the gastrointestinal tract of Narceus americana. Photo credit to C. Wright.

Bacteria from the gastrointestinal tract of Narceus americana. Photo credit to C. Wright.

Many organisms rely on gut-inhabiting bacteria to assist with the digestion of various foods. For example, detritivores, organisms that eat decaying organic matter in the soil, rely on bacteria for assistance in breaking down hard-to-digest plant material, such as cellulose (Taylor 1982). Many Enterobacteriaceae inhabit animal digestive systems and are known to assist with digestion (Lauzon et al. 2003). For a class project as an undergraduate, a fellow student (C. Wright) and I agar plated the gut contents of a common detritivore, the large North American millipede, Narceus americanus. After sequencing the 16S rRNA gene of the plated bacterial colonies, we discovered several members of Enterobacteriaceae inhabiting this millipede's gut including Bacillus mycoides, Serratia sp. and Enterobacter cloacae. All three of these bacteria were previously known to inhabit animal digestive tracts. B. mycoides was previously found in both the soil (Lewis 1932) and in earthworm guts (Jensen et al. 2003). Enterobacter cloacae is known from plants and insect digestive systems (Watanabe & Sato, 1998). Serratia has been recorded in the digestive tract of flies in the genus Dacus (Lloyd et al., 1986). It is possible that these bacteria are assisting this millipede species digest its food.

Several studies have examined the diversification of Enterobacteriaceae. Research indicates that the evolution of endosymbiotic forms occurred multiple times in this family (Husník et al. 2011). Additionally, many endosymbiotic Enterobacteriaceae coevolved with their hosts (Duchaud et al. 2003; Moran et al. 2005). Given their species diversity and the wide range of hosts they inhabit, Enterobacteriaceae are great organisms to study for understanding selective pressures on symbiotic relationships.


Beveridge, T.J. 2001. Use of the gram stain in microbiology. Biotechnic & Histochemistry 76: 111–118.

Duchaud, E., C. Rusniok, L. Frangeul, C. Buchrieser, A. Givaudan, S. Taourit, S. Bocs, C. Boursaux-Eude, M. Chandler, C. Jean-Francois and E. Dassa. 2003. The genome sequence of the entomopathogenic bacterium Photorhabdus luminescensNature biotechnology 21: 1307–1313.

Husník, F., T. Chrudimský & Václav Hypša. 2011. Multiple origins of endosymbiosis within the Enterobacteriaceae (γ-Proteobacteria): convergence of complex phylogenetic approaches. BMC biology 9: 87.

Janda, J.M. & S.L. Abbott. 2015. The family Enterobacteriaceae. Practical handbook of microbiology (Goldman, Emanuel and L. H. Greens, eds) 307–319.

Jensen, G.B., B.M. Hansen, J. Eilenberg & J. Mahillon. 2003. The hidden lifestyles of Bacillus cereus and relatives. Environmental microbiology 5: 631–640.

Lauzon, C. R., T. G. Bussert, R. E. Sjogren & R. J. Prokopy. 2003. Serratia marcescens as a bacterial pathogen of Rhagoletis pomonella fies (Diptera: Tephritidae). European Journal of Entomology 100: 87–92.

Lundgren, J. G., R. Michael Lehman & J. Chee-Sanford. 2007. Bacterial communities within digestive tracts of ground beetles (Coleoptera: Carabidae). Annals of the Entomological Society of America 100: 275–282.

Lewis, I.M. 1932. Dissociation and life cycle of Bacillus mycoides. Journal of bacteriology 24: 381–421.

Llyod, A.C., R.A.I. Drew, D.S. Teakle & A.C. Hayward. 1986. Bacteria associated with some Dacus species (Diptera: Tephritidae) and their host fruit in Queensland. Australian Journal of Biological Scienes 39: 361–368.

Moran, N.A., J.A. Russell, R. Koga and T. Fukatsu. 2005. Evolutionary relationships of three new species of Enterobacteriaceae living as symbionts of aphids and other insects. Applied and Environmental Microbiology 6: 3302–3310. 

Octavia, S. & R. Lan. 2014. The family enterobacteriaceae. The Prokaryotes: Gammaproteobacteria 225–286.

Taylor, E.C. 1982. Role of aerobic microbial populations in cellulose digestion by desert millipedes. Applied and environmental microbiology 44: 281–291.

Watanabe, K. & M. Sato. 1998. Plasmid-mediated gene transfer between insect-resident bacteria, Enterobacter cloacae, and plant-epiphytic bacteria, Erwinia herbicola, in guts of silkworm larvae. Current Microbiology 37: 352–355.

Squirrels (Sciuridae)

Maurice Chen

Sciurus carolinensis. Photo credit to Maurice Chen.

Sciurus carolinensis. Photo credit to Maurice Chen.

I was walking through Madison Square Park earlier this week when I was stopped in my path by a rather outgoing bushy-tailed rodent. We stared at each other for several seconds, neither one of us willing to turn back down the road we traveled. After a short time time, I decided to circle around and continue along my path, the whole time being barraged with disgruntled chittering noises as I didn't pay the proper toll in nuts or whatever food I had on me. Because of my encounter, I decided that this month we honor the squirrelly members of the Sciuridae famly.

There are 286 known species within the Sciuridae family (Waldheim 1817) which can be further categorized into three groups. They are tree squirrels, ground squirrels, and flying squirrels.(Bradford 2014) The squirrels that we most commonly see in New York City are the tree squirrels, Sciurus carolinensis, or Eastern Gray Squirrels. Squirrels can be found throughout the world except in Australia. Squirrels primarily eat non-cellulose plant matter, such as seeds, fruits, and conifer cones, however they are also known to eat fungi and occasionally insects (Thorington & Ferrel 2006).

If you decide to enjoy your lunch in Madison Square Park, don’t be surprised if a squirrel casually walks up to you and patiently waits for a portion of your meal. It’s not uncommon to see squirrels in Madison Square Park perched on benches sharing french fries with a recent Shake Shack customer. However, you might notice that there is a particularly high population of squirrels running around compared to most years. This is the result of the 2016 mast year. A mast year is a period where oaks produce a much higher volume of acorns. Oaks can yield up to 10 times the amount they produce in an average year. Scientists hypothesize that masting developed as a way to guarantee propagation in the presence of high predation (Savage 2016). If acorns are produced in high quantities during certain years, some of the acorns will survive unscathed since the level of predators cannot consume the excess amount. This concept is called predator satiation. Mast years seem to occur irregularly and predicting when they might occur have eluded the best scientists. What makes squirrels special is that they can somehow predict when a mast year is about to occur and will also change their mating behaviors accordingly (Boutin et al. 2006). Before a mast year, female squirrels will produce a second litter of offspring since food sources will be plentiful in the upcoming mast. This allows squirrel to have an advantage over many of the other organisms that forage acorns.

Squirrels play an important role in genetic composition of oak forests due to their foraging behaviors. Squirrels are more likely to bury, or “cache” acorns from red oaks while immediately eating acorns from white oaks. Red oak acorns tend to have a higher fat content and will last the winter before germinating in the spring. White oak acorns tend to germinate soon after falling from their parent tree and are sweeter, thus making them more ideal for immediate consumption. Squirrels will therefore cache red oak acorns up to 150 feet away from its parent tree resulting in expansive red oak forests with tight clusters of white oaks (Line 1999).

While acorns are the preferred food source for storing for the winter, squirrels will resort to other sources when acorn yields are low. Interestingly, squirrels will actually harvest fungi and dry them out into a jerky (Bittel 2014). Squirrels will also tap maple trees for their sap, eating the sugary syrup once the water content has evaporated (Roach 2005).


Bittel, J. 2014. 5 surprising facts about squirrels (hint: they make jerky). National Geographic

Boutin, S., L.A. Waters, A.G. McAdam, M. M. Humphries, G. Tosi & A. A. Dhondt. 2006. Anticipatory reproduction and population growth in seed predators. Science 314: 1928-1930

Bradford, A. 2014. Squirrels: diet, habits & other facts. Live Science

Line, L. 1999. When nature goes nuts: an astonishing array of animals is linked in some surprising ways to the mighty oak and its bounty. National Wildlife Federation

Roach, J. 2005. No nuts, no problem: squirrels harvest maple syrup. National Geographic

Savage, J. 2016. When is a tree smarter than a squirrel? Society for the Protection of New Hampshire Forests

Thorington, R. W. & K. Ferrell. 2006. Squirrels: the animal answer guide. John Hopkins University Press 75

Waldheim, F. 1817. Scuridae. Integrated Taxonomic Information System

Mountain Gorilla (Gorilla beringei beringei)

Harald Parzer

Dominant Silverback with wound due to a fight with a lone male. Photo credit to Harald Parzer.

Dominant Silverback with wound due to a fight with a lone male. Photo credit to Harald Parzer.

Mountain gorillas (Gorilla beringei beringei) are a subspecies of the Eastern Lowland Gorilla (Gorilla beringei) and are endemic to (or only found in) the mountainous region of the Albertine Rift in East Africa at an altitude from around 2200m to 4000m. They are found in two disjunct areas: the Virunga mountains, Rwanda and in Bwindi Impenetrable Forest, Uganda. Interestingly, these two populations behave quite differently. Bwindi Mountain Gorillas tend to climb much more and eat plenty of fruits, while the Virunga gorillas mostly stay on the ground and replace fruits with herbaceous stems. In fact, because of this, and morphological and genetic differences, some scientists argue that these populations represent two species, or at least two subspecies. Unfortunately, due to poaching and habitat destruction, only 880 individuals of this critically endangered species are left on this planet.

Mountain gorillas are incredibly powerful specimens to behold. They can grow to be as tall as an average man, with the same muscle and fat distribution, and weigh up to 430 lbs. Bodybuilders could only dream of such numbers. And yet, the mountain gorilla diet consist solely of plant matter! To maintain such weight, male mountain gorillas eat up to 34 kg of plants. Although they do not consume animal protein, about 18% of their overall food intake is protein from plant matter they select. Thus, an adult mountain gorilla can eat of up to 612 grams of protein every day far surpassing that of a bodybuilder's diet. Higher ranking females tend to have a higher caloric intake, not because they get nutrient richer plants, but because they tend to eat faster and are less active than their male counterparts.

Female mountain gorilla with her offspring. Photo credit to Harald Parzer.

Female mountain gorilla with her offspring. Photo credit to Harald Parzer.

Research shows that the home range of mountain gorillas changes with the seasons. In the dry season, mountain gorillas may increase their home ranges to 18 square miles in order to find their favorite plants (in Bwindi they have been observed to eat 107 species of plants). During the rainy season, the home ranges of mountain gorillas shrink dramatically as plants are more abundant and foraging doesn't require them to travel as far.

Mountain gorillas, which are either left or right handed in about the same proportions, live in small groups of around 10 individuals. The groups are composed of one to a few adult males, as well as females and juveniles of either sex. The dominant male, or silverback (named after his grey short hair on his back, which develops as a teenager), is almost twice as heavy as an adult female, and sires about 85% of the offspring if a second ranking silverback is in the group (who sires the remaining 15%). Thus, a silverback benefits from a large harem, as this means a lot of offspring. At times, like the group visited by the author in Bwindi Impenetrable Forest, older silverbacks are still hanging onto their group (and regularly get lost due to their slower pace...) and can be observed at the edge of it, old men observing the youth.

Infant mountain gorilla (about half a year old). Photo credit to Harald Parzer.

Infant mountain gorilla (about half a year old). Photo credit to Harald Parzer.

On average, a female produces 2.1–3.6 surviving offspring in her lifetime. Dominant females, which have higher lifespans, are producing more than lower ranking females. Infant mortality is high (21% of all infants won't make it to adulthood), mostly because of infanticide - yes, the ugly side of the mountain gorilla. When a new male takes over the group, after a vicious fights (see picture above) or natural death of the dominant silverback, the newcomer tends to kill all offspring to make sure that his harem is receptive for his own offspring. Thus, females prefer strong dominant males, which can protect their group as long as possible. Young males leave their groups when they are about 11 years old, and wander through the forest, mostly as lone males, to fight for a new group for themselves and that can take time.

Mountain gorillas, like all other gorillas, have not been observed to use tools in the wild, and have so far not been kept in zoos. Thus, if you want to meet this gentle giants, you will have to travel to Uganda or Rwanda, and join a gorilla trekking tour. The prices for such tours are steep ($600 for Bwindi National Park and $1500 for the Virunga Mountains), but they allow you to stay very close to one of the habituated groups for one hour. And you may even be hugged by a juvenile, as it happened to the trekking group of the author! These tours are well worth it and at least some of the money goes into protecting the habitat of the gorillas and to protecting other national parks, which are less frequently visited. So start saving money (cancel your TV subscription and write an essay for our upcoming competition to gain a few extra bucks), and get ready for a fantastic adventure! 


Bradley, B. J., M. M. Robbins, E. A. Williamson, H. D. Steklis, N. G. Steklis, N. Eckhardt, C. Boesch & L. Vigilant. 2005. Mountain gorilla tug-of-war: silverbacks have limited control over reproduction in multimale groups. Proceedings of the National Academy of Sciences of the United States of America 102: 9418–9423.

Robbins, M. M., A. M. Robbins, N. Gerald-Steklis & H. D. Steklis. 2007. Socioecological influences on the reproductive success of female mountain gorillas (Gorilla beringei beringei). Behavioral Ecology and Sociobiology 61: 919–931.

Rothman, J. M., A. J. Plumptre, E. S. Dierenfeld, & A. N. Pell. 2007. Nutritional composition of the diet of the gorilla (Gorilla beringei): a comparison between two montane habitats. Journal of Tropical Ecology 23: 673–682.

Zihlman, A. L., & R. K. McFarland. 2000. Body mass in lowland gorillas: a quantitative analysis. American Journal of Physical Anthropology 113: 61–78.

The Sea Robin (genus Prionotus)

Allison Bronson

Richard Gilder Graduate School, American Museum of Natural History, New York, U.S.A.

This month, while counting horseshoe crabs as part of the event, Monitoring Horseshoe Crab Breeding with NYC Audubon, the MSNH spotted a distinctive fish abandoned by fisherman along the shore - the sea robin (genus Prionotus). Part of the family Triglidae, sea robins are scorpaeniforms (scorpion fishes) that feed along the sea floor, and are quite common on the East Coast of the United States.

Part of the sea robin’s odd appearance is due to its little ‘legs’ – these are modified pectoral (chest) fin rays. Though it appears to walk on these spines, they are actually utilized for chemoreception, allowing the sea robin to ‘smell’ food hidden in the sand. The rest of the pectoral fin is probably how the sea robin got its common name – it fans out to make a beautiful ‘wing,’ visible in the photos that accompany this post. The sea robin can also produce a deep thumping sound, by using its swim bladder (a gas-filled internal sac) to amplify vibrations.

Most common sea robins (P. carolinus) only reach about a foot in length, though some have been noted at 16 inches. They are found near shore much more frequently in the summertime. In winter, they head for deeper waters. They are indiscriminate predators, consuming a remarkably wide range of invertebrates, as well as small fishes and algae.

Here in New York, sea robins are often sold as a fairly inexpensive fillet. Although the sea robin found by the MSNH had been rejected by some local fisherman, however, far from being ‘trash fish’ they are favored worldwide for traditional dishes like bouillabaisse (French fish soup). A simple sea robin recipe can be found at the On The Water article, Praise for Sea Robins. They’re a species of Least Concern (i.e. fairly abundant) and harmless to humans, so picking up a sea robin at the farmers market (or better yet, catching one yourself!) is a good way to sample our local New York City seafood.


Fishes of the Gulf of Maine: Sea Robin Northern Searobin


Eastern Tiger Swallowtail (Papilio glaucus)

Harald Parzer

Male. North Carolina, 2010. Photo Credit: Stephanie Loria.

Male. North Carolina, 2010. Photo Credit: Stephanie Loria.

Spring arrived, and along with it Papilio glaucus or the Eastern Tiger Swallowtail, one of our most spectacular butterflies. While adults feed on nectar of a wide variety of flowers, their caterpillars feed on leaves of Tulip trees (Liriodendron tulipifera), Black Cheeries (Prunus serotina), among many others. Choosy they are not!

The common name tells it all: this large butterfly, with a wingspan of up to 5.5 inches, belongs to the family of Swallowtails or Papilionidae (with over 570 species worldwide), and can be found in Eastern North America from Vermont to Florida, and show bold black stripes on their yellow wings (“tiger”), along with elegantly elongated tips at the end of their hindwings (“swallowtail”). They can be observed in a variety of habitats, including woodlands, fields, and in your garden, assuming you planted some butterfly-friendly (and hopefully native) flowers! For more information on how to do that, please see at the reference list.

After emergence from tiny green eggs, which the butterfly mom conveniently placed on their host trees, the caterpillars get right to business: first, they eat their egg shell (no waste in nature!), and then they use their large mandibles to chew up the leafs of their host tree. The caterpillar, which eventually will become about 1 ¼ inches before it pupates, is, unlike so many other swallowtail caterpillars, dull and green in appearance. The head itself has two rows of simple eyes, short antenna, and mandibles. The body has 13 segments, of which the first three form the thorax with a pair of true legs on each of them. Five of the other ten remaining segments have fleshy outgrowths which function as legs, keeping them stable on stems and leaves.

Given the essentially unlimited food supply, caterpillars get bigger by the minute. Like all arthropods, Eastern Tiger Swallowtails have their skeleton outside (“exoskeleton”), and thus have to replace this sturdy shell with an even bigger one, if they want to continue to grow. They do this by shedding their outer skin (“cuticula”) through a process called molting. Molting is orchestrated by a variety of insect hormones, including ecdysone and juvenile hormone. Once a caterpillar reaches a certain size, ecdysone is released, and in the presence of juvenile hormone it molts into another, larger caterpillar. However, with each molt, less and less juvenile hormone is released. And if the caterpillar was a good baby, and ate everything Mother Nature provided, the levels of juvenile hormone will eventually drop to such low levels, that when ecdysone rises once again, the caterpillar starts to pupate, instead of becoming another, even larger caterpillar.

And so it goes: the caterpillar, with lots of ecdysone, but little juvenile hormone, has one more bit of a tulip tree leaf, ejects whatever was not digested, and wanders to a safe spot where it molts into a pupa (“chrysalis”). Depending on the season, the pupa will metamorphose into our beloved Eastern Tiger Swallowtail within a few weeks (this species has up to three broods per year), or it overwinters, until spring returns.

Upon emergence, the careful observer can easily distinguish between males and females. While the hindwing of the male (figure above) has a dark black band along the edges, females have the same band with elegant blue spots, and usually also carry a slightly thicker “tail”. Interestingly, females come in two forms (“morphs”), depending on the region. In addition to the morph described above, females also have a dark morph in certain regions of the USA, and are thought to mimic the toxic Spicebush Swallowtail (Battus philenor), which is avoided by avian predators. As females refuse to mate with males who try get away with the same disguise, males are stuck with the conspicuous tiger pattern, attractive to female Tiger Swallowtails, humans, and birds alike.

You might also be able to observe (young) males congregating at puddles, mud, and even dung and carrion, a behavior which is called “puddling”. They do this to extract additional sodium ions and amino acids, as nectar is full of sugar, but not much else. And, like good gentlemen, they present this gift to their lady to give their offspring a head start. In fact, it has been shown that males who are able to provide more sodium, will allow the female to have more offspring.

Next time you see one, ask yourself: is it a male or female? Which morph? And if you have a little garden available, why not welcome them with a native flower bouquet!


Belth, J. E. 2013. Butterflies of Indiana – A Field Guide. Indiana University Press, Bloomington.

NABA-North Jersey Butterfly Club. 2017. New Jersey Butterflies – Eastern Tiger Swallowtail (

NABA-North Jersey Butterfly Club. 2017. Creating a butterfly garden (

Atlantic Horseshoe Crab (Limulus polyphemus)

Stephanie F. Loria

This month we honor an organism which will soon begin its breeding season in NYC - the Atlantic horseshoe crab, Limulus polyphemus. Despite their name and superficial resemblance, horseshoe crabs are not crabs. They actually belong to their own class Xiphosura in Chelicerata, an arthropod group that also includes the classes Arachnida (spiders, scorpions, ticks, etc), Eurypterida (the extinct sea scorpions and also MSNH's logo taxon), and Pycnogonida (sea spiders). The placement of Xiphosura within Chelicerata has been debated and recent research has even placed Xiphosura within Arachnida (Sharma et al. 2014). Worldwide only four extant species of horseshoe crabs exist and all species except L. polyphemus are found in the Indo-Pacific Ocean (Xia 2000). Extinct horseshoe crab species have also been described and the oldest fossil, found in Canada, dates to the Upper Ordovician, 445 million years ago (Rudkin et al. 2008)! Despite their remarkably old age, horseshoe crabs have changed little morphologically since their first appearance and are therefore often referred to as 'living fossils' in the scientific literature (Avise et al. 1994). 

The breeding season of L. polyphemus runs from March to July with peak season occurring in May and June (Rudloe 1980; Rutecki et al. 2004). During the breeding season, male and female L. polyphemus arrive on the shores of eastern North America in droves with most breeding happening at high tide on new and full moon nights (Rudloe 1980). Males typically mount females using special claspers and eggs are fertilized externally (Brockmann 1990). However, eggs may also be fertilized by satellite males which are not attached to females and surround the mating couple (Sasson et al. 2015). Eggs develop in the sand, hatching 3 to 4 weeks later and larvae disperse into the ocean (Bakker et al. 2016; Botton and Loveland, 2003; Rudloe, 1979). Horseshoe crabs live longer than dogs typically reaching 19 years of age (Rutecki et al. 2004).

During the breeding season, red knots (Calidris canutus rufa) feast on horseshoe crab eggs, an important food source for these birds (Niles et al. 2009). Horseshoe crabs are also harvested by humans for biomedical use as their blood contains amoebocyte lysate (ACL), a compound that can be used to detect bacterial endotoxins (Rutecki et al. 2004). Although biomedically harvested individuals are typically released once blood has been taken, mortality does occur among released individuals (Rutecki et al. 2004). Horseshoe crabs are also harvested for fishing bait and overharvesting from fishing and the biomedical industry and shoreline destruction has led to population declines (Land et al. 2015). In order to help track the health of horseshoe crab populations, nonprofit organizations such as NYC Audobon, and researchers survey horseshoe crabs populations each year during the breeding season. This year, the MSNH will team up again with NYC Audubon on Friday, June 9 to participate in the survey so that we can interact and help protect this fascinating and ancient species.

Horseshoe crabs (L. polyphemus) at Jamaica Bay. Courtesy of Maurice Chen.

Horseshoe crabs (L. polyphemus) at Jamaica Bay. Courtesy of Maurice Chen.


Avise, J. C., W. S. Nelson, and H. Sugita. 1994. A speciational history of" living fossils": molecular evolutionary patterns in horseshoe crabs. Evolution: 1986-2001.

Bakker, A. K., J. Dutton, M.  Sclafani and N. Santangelo. 2016. Environmental exposure of Atlantic horseshoe crab (Limulus polyphemus) early life stages to essential trace elements. Science of The Total Environment 572: 804-812.

Botton, M. L. and R. E. Loveland. 2003. Abundance and dispersal potential of horseshoe crab (Limulus polyphemus) larvae in the Delaware estuary. Estuaries 26: 1472-1479.

Brockmann, H. J. 1990. Mating behavior of horseshoe crabs, Limulus polyphemusBehaviour 114: 206-220.

Landi, A. A., J. C. Vokoun, P. Howell, and P. Auster. 2015. Predicting use of habitat patches by spawning horseshoe crabs (Limulus polyphemus) along a complex coastline with field surveys and geospatial analyses. Aquatic Conservation: Marine and Freshwater Ecosystems. 25: 380-395.

Niles, L. J ., J. Bart, H. P. Sitters, A. D. Dey, K. E. Clark, P. W. Atkinson, A. J. Baker, K. A. Bennett, K. S. Kalasz, N. A. Clark, and J. Clark. 2009. Effects of horseshoe crab harvest in Delaware Bay on Red Knots: are harvest restrictions working? Bioscience59: 153-164.

Rudkin, D. M., G. A.  Young, and G. S. Nowlan. 2008. The oldest horseshoe crab: a new Xiphosurid from Late Ordovician Konservat‐Lagerstätten Deposits, Manitoba, Canada. Palaeontology 51: 1-9.

Rudloe, A. 1979. Locomotor and light responses of larvae of the horseshoe crab, Limulus polyphemus (L.). The Biological Bulletin 157: 494-505.

Rudloe, A. 1980. The breeding behavior and patterns of movement of horseshoe crabs, Limulus polyphemus, in the vicinity of breeding beaches in Apalachee Bay, Florida. Estuaries and Coasts 3: 177-183.

Rutecki, D., R. H. Carmichael, and I. Valiela. 2004. Magnitude of harvest of Atlantic horseshoe crabs, Limulus polyphemus, in Pleasant Bay, Massachusetts. Estuaries and Coasts 27: 179-187.

Sasson, D. A., S. L. Johnson, and H. J. Brockmann. 2015. Reproductive tactics and mating contexts affect sperm traits in horseshoe crabs (Limulus polyphemus). Behavioral ecology and sociobiology 69: 1769-1778.

Sharma, P. P., S. T. Kaluziak, A. R. Pérez-Porro, V. L. González, G. Hormiga, W. C. Wheeler, and G. Giribet. 2014. Phylogenomic interrogation of Arachnida reveals systemic conflicts in phylogenetic signal. Molecular Biology and Evolution, p.msu235.

Xia, X. 2000. Phylogenetic relationship among horseshoe crab species: effect of substitution models on phylogenetic analyses. Systematic Biology 49: 87-100.

Cannonball Jellyfish (Stomolophus meleagris)

Stephanie F. Loria

With the diversity of life in the ocean still largely unknown, this month we honor a marine organism, the cannonball jellyfish (Stomolophus meleagris). Cannonball jellies, like other jellyfish belong to the phylum Cnidaria, one of the oldest animal lineages originating approximately 740 million years ago (Park et al. 2012). During their life cycle, most cnidarians exhibit two different morphological forms: the motile medusa stage (aka the typical jellyfish form) and the sessile polyp stage (like sea anemones). For jellyfish, the medusa is the sexually reproducing form and most jellyfish species are dioecious meaning that each medusa is either male or female and not hermaphroditic. Male medusae release sperm into the water which fertilize eggs externally or internally in female medusae. Fertilized eggs hatch to form larvae that can then travel long distances to find a substrate to attach to and metamorphosize into the polyp form. Polyps later transform into medusae and the life cycle repeats.

To feed, cnidarians use nematocysts (stinging cells which look like they have tiny barbs) on their tentacles to paralyze prey and then digest the prey using enzymes in a gastrovascular cavity. As jellyfish have no anus, all food must enter and leave through the same opening. Cannonball jellyfish, although found across the world's oceans are most common on the southeastern coast of North America (Wikipedia). If you find yourself walking along the beaches in South Carolina, a state where these jellyfish are quite common, you might see some washed-up cannonball jellies with tiny crabs on them as depicted in the image below. These juvenile spiders crabs (Libinia dubia) are not eating the dead jellyfish but are rather cast away in a catastrophic jellyfish shipwreck. The juvenile spider crabs have a symbiotic relationship with the cannonball jellyfish, sharing its food and using it for protection (Afford & Patel). 

The future of cannonball jellyfish populations is uncertain as this North American species has become a delicacy in Asia and business has been booming (Narula 2014). Carolinan fishing companies are harvesting these jellyfish via trawling and shipping them to the other side of the world to be sold in fish markets (Narula 2014). The profits from harvesting jellyfish are enormous, with some fisherman making 10000 USD per day (Narula 2014). However, the ecological impacts of harvesting cannonball jellyfish may soon be realized as environmental groups warn that excessive trawling and pollution from jellyfish processing plants may outweigh the monetary benefits to local communities (Narula 2014). 

Cannonball jellyfish with juvenile spider crab. Hilton Head Island, S.C. Photo Credit: Stephanie Loria.

Cannonball jellyfish with juvenile spider crab. Hilton Head Island, S.C. Photo Credit: Stephanie Loria.


Afford, H. & T. Patel. Stomolophus meleagris, cannonball jellyfish. Animal Diversity Web. University of Michigan, Museum of Zoology.

Narula, S. K. 2014. 'Jellyballs' are serious business. The Atlantic.

Park, E., D. S. Hwang, J. S. Lee, J. I. Song, T. K. Seo & Y. J. Won. 2012. Estimation of divergence times in cnidarian evolution based on mitochondrial protein-coding genes and the fossil record. Molecular phylogenetics and evolution. 62: 329-345.

Cannonball Jellyfish. Wikipedia.


Snowy Owl (Bubo scandiacus)

Harald Parzer

Male snowy owl. By Michael Gäbler, CC BY-SA 3.0, from Wikimedia Commons.

Male snowy owl. By Michael Gäbler, CC BY-SA 3.0, from Wikimedia Commons.

Ever since the arrival of Harry Potter, children, teenagers, and even adults (you know who you are!), inquire at pet stores on how to adopt a snowy owl (Bubo scandiacus). What books and movies forgot to mention is that keeping a snowy owl is not an easy task.

First, snowy owls are adapted to the bitter dry-cold environment of the North American and Eurasian Arctic. You better have a well air conditioned aviary for your new pet! Second, snowy owls are nomads and can mass migrate – quite unpredictably – as far south as Florida and Texas. So, do not leave your aviary open! Thirdly, snowy owls are fierce predators, which require plenty of bird and mammal meat to feed themselves and their young (7-12 small rodents/day). Like other owls, they swallow their prey as a whole, allowing strong stomach juices to digest the flesh, only to regurgitate the remnants as ugly pellets. And who will clean that?

But pretty they are: males develop an almost snow-white plumage, while females are primarily white with some black spots. These owls see the world through mesmerizing yellow eyes, and have a sharp black beak, both of which are important adaptations to their predatory life style. Among the 164 species of owls, Bubo scandiacus is one of the largest, with a wingspan of up to 59 inches (52 inches average) and a weight of up to 6.6 lbs (4 lbs average). Like many raptors, females are usually larger than males, possibly to maximize egg production. As a rare exception among owls (which mostly use either tree cavities or abandoned nests of other species to breed), the snowy owl is building its own nest in the Arctic tundra. Usually, one can find such nests at elevated spots with little vegetation, which this fierce animal uses to defend its 5 – 10 eggs whenever a predator approaches. Be aware!

While snowy owls can be found year round in the Arctic Circle, even during polar nights, some of them may abruptly leave their wintering grounds to the more pleasant South, waiting there to return until the harsh Arctic winter is receding. During such southern vacations, snowy owls also choose the Big Apple as their winter destination. Like so many humans, these owls do not want to miss the comfort of their home, and thus are settling primarily in areas which resemble the Arctic tundra. As such, snowy owls can be found every winter at open areas with little vegetation on beaches, like Rhiis Beach, Floyd Bennett Field, or even JFK airport. While the winter of 2017 has not yet been proven to be an exceptional snow-owly year for NYC, many sighting have been made in 2014, when more than 20 different owls have been confirmed. But watch out - time to clean your binoculars, prepare yourself to see a rare visitor from the North: in January birdwatchers reported a sighting at the tip of Breezy Point, and several sightings of an individual have been made at Sandy Hook in February.


Holt, D.W., M. D. Larson, N. Smith, D. L. Evans and D. F. Parmalee. 2015. Snowy Owl (Bubo scandiacus), The Birds of North America (P. G. Rodewald, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America

Leonard, P. 2014. A Season of Snowy Owls. Living Bird Magazine.

Tuft, D. 2015. Amid Urban Debris, the Snowy Owl Is a Wintertime Ghost. The New York Times.


Critically Endangered Cabbage on a Stick (Brighamia insignis)

Allison Bronson

Richard Gilder Graduate School, American Museum of Natural History, New York, U.S.A.

Take one look at Brighamia insignis, and you’ll see how it got the nicknames “cabbage on a stick” and “cabbage on a baseball bat.” Its quirky appearance aside, this member of the family Campanulaceae is an emblem of conservation in the face of extreme adversity on the islands of Kauaʻi and Niʻihau.

Photo Credit: Wikimedia commons. By C.T. Johansson.

Photo Credit: Wikimedia commons. By C.T. Johansson.

Brighamia is commonly known as the Hawaiian or Vulcan palm, despite having no relation to the palm family (Arecaceae). The ‘palm’ can grow to be 16 feet tall, but usually stands about three to six feet, and makes its home on rocky cliffs of volcanic soil. The plant is endemic to Hawaii – that is, it grows nowhere else on earth, and co-evolved with its pollinator, a species of endemic Hawaiian hawk moth. The hawk moth’s long proboscis was just the right length to reach into the plant’s long, tube-like flowers. In the last century, this hawk moth went extinct (for unknown reasons) and Brighamia was left with no way to distribute its pollen and produce offspring.

The loss of its pollinator only compounded the challenges faced by Brighamia. Like many native Hawaiian species, introduced taxa took a significant toll on the plant’s populations. While feral pigs and goats ate the plants, invasive plants colonized areas barren from fire and competed with Brighamia for space and resources. Perhaps most devastating were introduced spider mites (Tetranychus cinnabarinus), to which Brighamia is particularly susceptible. 
Despite conservation efforts to mitigate these problems, two hurricanes (1982 and 1992) blew many of the surviving plants off their cliffs. In previous years, five populations of this plant were recorded in the wild, each between 45 and 65 individuals. Sadly, as of last year, workers observing these populations believe there may be only a single plant left on the island of Kauaʻi.

Fortunately for Brighamia, its weird appearance has charmed conservationists and horticulturists alike, and extraordinary steps have been taken to bring this plant back from the brink. Scientists and volunteers even rappel down cliffs in order to hand-pollinate the plants, and to retrieve seeds to grow in greenhouses. The cabbage-on-a-stick is commonly bred as an ornamental plant and has become popular among plant enthusiasts worldwide, but despite its success in ‘captivity,’ the plant will never succeed in the wild without a pollinator. So Brighamia is a particular type of oddity: a unique morphology honed over millions of years of isolated island evolution, toppled by a changing environment, and preserved as a relict curiosity among human collections, hopefully to inspire fierce protection of the environment and preservation of endemic species.

Lewis, R. 2016. Down to the last plant: The painstaking work of extinction preventionFusion.

Wong, J. 2016. 2016. All Hail the Vulcan Palm. The Guardian.

University of Hawaii. Brighamia insignisNative Plants Hawaii.

Botanist works to save Hawaii’s rare plants. 2014. VOA News.