Behind the cover: orchid bee genome
A green, iridescent bee perches on a pink flower, extending its proboscis to reach the sweet nectar inside. He’s not just after a meal—he’s also collecting fragrant substances to store inside his hollow rear legs. Later, he’ll buzz his wings to release the aroma with the hope of attracting a mate. The cover of the September issue of G3 features a photograph of this eye-catching insect: a type of orchid bee called Euglossa dilemma. Orchid bees inhabit the neotropical realm, a region encompassing most of South America, some of Central America, and a tiny fraction of southern North America. There, these bees are some of the most important pollinators of flowering plants.
In the same issue of G3, Brand et al. report a draft assembly of the nuclear and mitochondrial genome of E. dilemma, the first draft genome of any species in the genus Euglossa. The genome revealed several interesting facts about the bees; for example, they have one of the largest genomes of any insect, loaded with repetitive sequences. Their assembly will also be a boon to bee researchers, from those seeking to know more about how to conserve these essential pollinators to those studying bee evolution.
Of particular interest is the evolution of one of many bees’ most fascinating traits: the ability to form intricate social structures. E. dilemma, unlike its close relatives the honeybee, stingless bee, and bumble bee, doesn’t actually live in communal hives. If the male orchid bee succeeds in seducing a female with his foraged scents, she’ll lay their eggs in a small nest of up to twenty cells, where she’ll feed the larvae nectar and pollen. Orchid bees may build their nests near each other, giving the impression of a loosely connected society, but groups of nests don’t form communities like hives. However, daughter bees sometimes stay in their mothers’ nests to help her raise a new generation—a type of social interaction that may have been one of the evolutionary stepping stones toward hives in insects like honeybees. Using the new genome as a starting point, researchers might be able to learn more about the evolution of this complex behavior, increasing our knowledge of many more types of these industrious insects.
Brand, P.; Saleh, N.; Pan, H.; Li, C.; Kapheim, K.; Ramírez, S. The Nuclear and Mitochondrial Genomes of the Facultatively Eusocial Orchid Bee Euglossa dilemma.
G3: Genes|Genomes|Genetics, 7(9), 2891-2898.