May 12, 2019
This a work in progress, but because of illness, there have been no recent additions to the document and it is not clear how much progress will occur in near future.
Hopefully, I will remember to change the date above with every edit or addition.
Melittology is the study of bees- any of the approximately 20,000 species in the generally recognized six or seven families.
Amateurs can be important contributors to the study of insects and bees. According to the British organization, Amateur Entomologists’ Society which studies insects, amateurs have contributed most of the biological records in the United Kingdom and, unlike professionals are not limited by short term funding. Other countries or localities could benefit from the British example. The page “Why are amateur entomologists so crucial to biodiversity and biological recording? ” is available at:
In some places and in certain situations, the collection of insects and other invertebrates is regulated. Follow the regulations that apply.
In his book, Bees of the World, second edition, published in 2007, the late, highly respected entomologist and melittologist, Charles Michener, listed the families as Stenotritidae, Colletidae, Andrenidae, Halictidae, Melittidae, Megachilidae, and Apidae. It can be found at: http://base.dnsgb.com.ua/files/book/Agriculture/Beekeeping/Thep-Bees-of-the-World.pdf
The genus Apis with about seven honey bee species is included in the family Apidae. Michener wrote, “Persons studying bees other than Apis (honey bees) and concerned about the negative and awkward expression “non-Apis bees” would do well to call themselves melittologists and their field of study melittology.”
There is a steep learning curve when one begins to learn about non-Apis bees. There are only a few entomologists that specialize in non-Apis bees and they don’t always use the same terminology or even classify bees in the same families. For example, in their book, Bees of the World,” paperback edition published in 1999, Christopher O’Toole and Anthony Raw list eleven families of bees- Stenotritidae, Colletidae, Halictidae, Oxaeidae, Andrenidae, Melittidae, Ctenoplectridae, Fideliidae, Megachilidae, Anthophoridae. and Apidae. For most Americans, the differences in classification will be most confusing in the bee genera which O’Toole and Raw classify as Anthophoridae rather than Apidae.
There is at least one other approach to the classification of bee families. An October 10, 2006 paper, “The history of early bee diversification based on five genes plus morphology,” by Brian Danforth, Sedonia Sipes, Jennifer Fang, and Sean Brady, lists nine families. The paper classifies Dasypodaidae and Meganomiidae as families. On July 27, 2018, according to Google Scholar, that paper had been cited 251 times.
A 2013 opinion piece, “Obtaining a better taxonomic understanding of native bees: where do we start?” by Victor Gonzalez, Terry Griswold, and Michael Engel states,
“The most widely accepted classification for bees recognizes 7 extant families, 21 subfamilies, 50 tribes and about 450 genera worldwide.”
Why are there different classification schemes? Because so many characteristics pop-up in different bee species in ways that make relatedness debatable.
An example of shared characteristics in otherwise quite dissimilar bees-the bees in the family Andrenidae and bees in the genus Anthophora and in the family Apidae (or, depending on who is doing the classification, the family Anthiphoridae) both burrow in the ground, but Andrenidae have short tongues and Anthophora have long tongues. Tongue length and other characteristics place them in separate families.
All bees have two names- a genus name and a species name, often followed by the name of the person who first published a description and named it. For example, Bombus vosnesenskii, Radoszkowski, is a bee in the genus Bombus, the genus of bumblebees. The species is vosnesenskii. This bee has a common name- Yellow-faced Bumble Bee- but many bees do not. It is convention to italicize both the genus and the species name and capitalize the genus name. Often texts will abbreviate the name so that Bombus vosnesenskii is referred to as B. vosnesenskii.
Further notes on classification-
What is a species? In an article in ScienceNews, “Defining ‘species’ is a fuzzy art,” Susan Milius writes,
“At first glance, “species” is a basic vocabulary word schoolchildren can ace on a test by reciting something close to: a group of living things that create fertile offspring when mating with each other but not when mating with outsiders. Ask scientists who devote careers to designating those species, however, and there’s no typical answer. Scientists do not agree.”
She relates some of the ways scientists have told her how that definition is inadequate. With bees, the school book definition of species is usually adequate.
The Convention on Biological Diversity has a web page called “What is Taxonomy?” where it states,
“Taxonomy is the science of naming, describing and classifying organisms and includes all plants, animals and microorganisms of the world. Using morphological, behavioural, genetic and biochemical observations, taxonomists identify, describe and arrange species into classifications,…”
That page can be found at: https://www.cbd.int/gti/taxonomy.shtml
They have another page, “Why is Taxonomy Important?,” which states,
“Global biodiversity is being lost at an unprecedented rate as a result of human activities, and decisions must be taken now to combat this trend. But how do decision-makers decide where to establish protected areas if they don’t know what is being protected? How can regulators identify and combat harmful invasive species if they cannot distinguish them from native species? How do developing countries ensure that they reap the benefits of the use of their biological diversity, if they don’t know the biological diversity that is being used? Taxonomy provides basic understanding about the components of biodiversity which is necessary for effective decision-making about conservation and sustainable use.”
That page can be found at: https://www.cbd.int/gti/importance.shtml
If you do much reading of scientific papers on bees, you are likely to come across the terms phylogenetic trees, classes, and cladograms.
The Entomology 425 tutorial by North Carolina State University (NCSU) author, John Meyer, has a page called “Introduction to Systematics” and a page called “Phylogenetic Trees” which can be found at: https://projects.ncsu.edu/cals/course/ent425/library/tutorials/systematics_taxonomy/phylogenetic_trees.html
Dr. Meyer wrote,
“Just as a geneologist might construct a family tree to illustrate ancestors and descendents within a human family, systematic biologists (taxonomists) construct phylogenetic trees to depict relationships among groups of living organisms. There are several ways to create such trees. The method chosen often depends on the distinctiveness of each taxon, the type and quality of categorical data available, and the scientist’s overall philosophy toward classification.”
The University of California at Berkeley has a website, “Understanding Evolution,” with a page called “Evolutionary trees: A primer” which can be found at: https://evolution.berkeley.edu/evolibrary/article/0_0_0/evotrees_primer_01.
The site includes a page called “Reading trees: A quick review which can be found at: https://evolution.berkeley.edu/evolibrary/article/phylogenetics_02. It asks the question,
“What’s the difference between a phylogeny, an evolutionary tree, a phylogenetic tree, and a cladogram?
For general purposes, not much. This site, along with many biologists, use these terms interchangeably — all of them essentially mean a tree structure that represents the evolutionary relationships within a group of organisms. The context in which the term is used will tell you more details about the representation (e.g., whether the tree’s branch lengths represent nothing at all, genetic differences, or time; whether the phylogeny represents a reconstructed hypothesis about the history or the organisms or an actual record of that history; etc.) However, some biologists do use these words in more specific ways. To some biologists, use of the term “cladogram” emphasizes that the diagram represents a hypothesis about the actual evolutionary history of a group, while “phylogenies” represent true evolutionary history. To other biologists, “cladogram” suggests that the lengths of the branches in the diagram are arbitrary, while in a “phylogeny,” the branch lengths indicate the amount of character change. The words “phylogram” and “dendrogram” are also sometimes used to mean the same sort of thing with slight variations. These vocabulary differences are subtle and are not consistently used within the biological community. For our purposes here, the important things to remember are that organisms are related and that we can represent those relationships (and our hypotheses about them) with tree structures.”
Sam Droege (of the USGS Patuxent Wildlife Research Center) has taken some stunning photos of bee specimens in public collections. These can be found at: https://www.flickr.com/search/?user_id=54563451%40N08&sort=date-taken-desc&view_all=1&text=Hymenoptera You can replace “Hymenoptera” in the link with various bee genera and such.
The photos of bees on Sharp-Eatman Nature Photography’s website illustrate the diversity of bee species that can be found in one location. See https://www.sharpeatmanguides.com/wild-bee-id-guide-new-york.
Bees are members of the phylum Arthropoda.
According to “Basic Entomology” by Janet Spenser of the Virginia Cooperative Extension at: https://hampton.ext.vt.edu/content/dam/hampton_ext_vt_edu/entomology.pdf
“ Segmented body
Tubular alimentary system, with mouth & anus
Open circulatory system
Respiration by gills, trachea, or spiracles
Sexes are almost always separate”
The AES glossary defines an exoskeleton as,
“a skeleton that is on the outside and encases all the muscles and organs of an organism.”
The North Carolina State University Entomology tutorial has a page on the exoskeleton which describes the composition of exoskeleton and the process of molting. It can be found at: https://projects.ncsu.edu/cals/course/ent425/library/tutorials/external_anatomy/exoskeleton.html
On the tutorial page on the exoskeleton, Dr. Meyer writes.
“An insect’s exoskeleton (integument) serves not only as a protective covering over the body, but also as a surface for muscle attachment, a water-tight barrier against desiccation, and a sensory interface with the environment.”
According to Murat Kaya et al, in “Differentiations of Chitin Content and Surface Morphologies of Chitins Extracted from Male and Female Grasshopper Species,” chitins have been found in insects, anthozoans, sponges, crabs, shrimps, crayfish, small crustaceans, myriapods, arachnids and also in the cell structure of algae and yeast, and in the cell walls of fungi and mushrooms. The article stated,
“Chitin (C8 H 13 O5 N)n is a natural polysaccharide and is the second most abundant biopolymer after cellulose.’
The study described in the article found, among other things, that male grasshoppers had more chitin than female grasshoppers.
Another study, published as “Fluctuation in physicochemical properties of chitins extracted from different body parts of honeybee,” by Murat Kaya et al, found that the head, thorax, abdomen, legs and wings of the honeybee have different chitin content.
An article, “Tolerance requires the Right Smell: First Evidence for Interspecific Selection on Chemical Recognition Cues,” by Florian Menzel and Thomas Schmitt states,
The integument of insects is generally covered with cuticular hydrocarbons (CHC). They serve multiple functions, most prominent among them waterproofing and—especially among social insects—as communication signal. CHC profiles are incredibly diverse within and across species…
Additionally, in many insect species, CHC are an important means to transport information on its bearer, such as its species membership and sex… In social insects, CHC transmit a plethora of other information in addition—of its carrier’s colony membership…, its task within the colony…, and its reproductive status (fertility signal…)
More information on the cuticular hydrocarbons see, “How do cuticular hydrocarbons evolve? Physiological constraints and climatic and biotic selection pressures act on a complex functional trait,” by Florian Menzel, Bonnie B. Blaimer, and Thomas Schmitt which can be found at: http://rspb.royalsocietypublishing.org/content/royprsb/284/1850/20161727.full.pdf.
“Ecology and Evolution of Communication in Social Insects,” by Sara Diana Leonhardt, Florian Menzel, Volker Nehring, and Thomas Schmitt which can be found at: https://www.cell.com/action/showPdf?pii=S0092-8674%2816%2930049-6
The plates of the exoskeleton are called sclerites.
According to the AES,
Spiracles are respiratory openings found on the thorax and abdomen of insects. The spiracles are connected to trachea – tubes within the insect’s body…. Insect blood, haemolymph, is not used to transfer oxygen around the body of the insect….
“The trachea are part of the respiratory system of insects. Air enters the insect’s body through the spiracle and enters the trachea. The trachea are tubes that are strengthened by rings of cuticle. From the trachea the air moves into smaller tubes called tracheoles that spread throughout the body of the insect and allow oxygen to be delivered to the various parts of the body.”
Bees are insects (Class Insecta).
According to the Entomology 425 tutorial by North Carolina State University (NCSU) author, John Meyer, there are 800,000 described species of insects. In the tutorial he writes,
” Entomologists describe hundreds of these new species each year, and still estimate that only one-half to one-third of the earth’s total insect fauna has even yet been discovered. In the final analysis, two of every three living species may be insects.”
On the first page of the “Index to the Compendium of Hexapod Classes and Orders ” of Entomology 425 includes the list the 28 orders of Insects (Class Insecta). It can be found at https://projects.ncsu.edu/cals/course/ent425/library/compendium/index.html.
We know mostly about those few insect species that are pests and very little, if anything at all, about how the majority function in ecosystems. Scientists do know that healthy soils are dependent on them, the ground burrowing ones aerate soils, some recycle wastes, some are responsible for most pollination of flowering plants, and some are food for birds, and other animals.
The British organization, the Amateur Entomologists’ Society (AES), has a glossary which can be found at https://www.amentsoc.org/insects/glossary/.
The University of California at Riverside (UCR) has an entomology glossary which can be found at http://www.faculty.ucr.edu/~legneref/biotact/glossary.htm.
Many publications describe and picture or illustrate the external characteristics of many insect and bees species. North Carolina State University” has a Cliff Notes” type entomology website which describes the internal anatomy and physiology of insects. It can be found online at https://projects.ncsu.edu/cals/course/ent425/index.html.
According to the AES, three of the most easily recognized characteristics of insects are that they have three body parts (a head, thorax, and abdomen), two pair of wings, and three pair of legs. As with many generalizations, the generalization that all insects have have two pair of wings can be confusing because of the exceptions- In comparing the appearance of flies to bees, flies are often referred to as only having a pair of wings because halteres are stubby. Beetles and earwigs have elytra or hardened forewings. The worker caste in ants and a few female wasp species are wingless. An observer can easily see that there are two separate wings on each side of a dragonfly, but because the fore wing and hind wing of bees and wasps are hooked together in flight, the casual observer may not realize there are two wings on each side.
According to “FAO’s Global Action on Pollination Services for Sustainable Agriculture” Glossary found at http://www.fao.org/pollination/resources/glossary/en/
The head is “The foremost of the three major body segments of insects,” the thorax is “The central of an insects three major body segments, and the one to which wings and legs are attached,” and the abdomen is “The hindmost of an insects three body segments, in which most vital organs are located.”
As arthropods, insects have exoskeletons. In order to grow, they must molt (shed), their hardened skin (their exoskeleton). Nearly all insects go through metamorphosis. Some basically just get larger with every molt after they emerge from the egg. This is called ametabolous metamorphosis. Other insects look similar to adults after they emerge from the egg but the wings and sexual organs develop later. This is called hemimetabolous metamorphosis.
Other insects including bees go through complete metamorphosis (holometabolous metamorphosis) – egg, larval, pupal, and adult stages looking distinctly different, but the time spent in each stage varies with the species and the environmental conditions. The larval stage is spent eating and growing. The pupal stage is spent transforming. Some adults mate and some adult females lay eggs.
According to AES, an instar is,
“an immature arthropod between moults.”
The conditions and the time when the adult bee emerges from the nest have been studied in a few species, but are not well understood. With climate change, scientists are concerned that the timing of that flowers need pollination may not be in sync with the time those particular flowers’ pollinators emerge.
In one study, “Effect of Wintering Duration and Temperature on Survival and Emergence Time in Males of the Orchard Pollinator Osmia lignaria (Hymenoptera: Megachilidae),” by Jordi Bosch and William P. Kemp, male Osmia lignaria survival was related to wintering duration and temperature. The common name for this bee is the Blue Orchard Bee. This bee is an extremely efficient pollinator and the study was attempting to find ways to time the bee’s emergence as an adult with the crops it might pollinate as a managed pollinator.
In another study, “Metamorphosis is induced by food absence rather than
a critical weight in the solitary bee, Osmia lignaria,” by Bryan R. Helm et al, the “larvae initiated pupation less than 24 hours after food was absent.
It was once believed that insects are cold-blooded, but Bernd Heinrich found ways to measure the temperature of insects and now we know that insect thermoregulation physiology and behavior varies considerably among insect species. Some insects and most bee species go into a state called diapause, a state of arrested development, which may occur any time of year. It usually occurs in the immature stages before the bee emerges as a mature adult. Some experiments with bumblebees have shown that at times the temperatures of the thorax and the abdomen can vary considerably, depending on the circumstances. Bumble bee workers appeared less able to regulate their temperatures than queens. A bumblebee species in the Artic uses an antifreeze like chemical to survive the long, cold winters. A google scholar search on “Bernd Heinrich” and “thermoregulation”will bring up links to a number of papers he authored or co-authored on the subject. The abstracts or summaries are free.
Insects have compound eyes meaning the eyes have multiple lenses called ommatidium. A study in bees, described in “Allometry and resolution of bee eyes” by Ursula Jander and Rudolf Jander, found that the number of lenses was proportional to the body size and that the “eyes of nocturnal foragers had about 1.8 times the surface area as compared with diurnal foragers of matching size.” Bees also have three simple eyes on top of their heads called ocelli which scientists believe help the bee adjust to light levels as they fly in and out of shade.
Bees are insects in the scientific order, Hymenoptera.
The opening paragraph of the abstract of the article, “Evolutionary History of the Hymenoptera” found at https://www.researchgate.net/publication/315546400_Evolutionary_History_of_the_Hymenoptera, states,
“Hymenoptera (sawflies, wasps, ants, and bees) are one of four mega-diverse insect orders, comprising more than 153,000 described and possibly up to one million undescribed extant species. As parasitoids, predators, and pollinators, Hymenoptera play a fundamental role in virtually all terrestrial ecosystems and are of substantial economic importance.
According to Hymenoptera of the world: An identification guide to families edited by Henri Goulet and John T. Huber, one characteristic of Hymenoptera is that females are develop from diploid (fertilized) eggs and males from haploid (unfertilized) ones. Hymenoptera of the world: An identification guide to families has an illustrated glossary beginning on page 34. It can be found at https://cfs.nrcan.gc.ca/publications?id=35617
In his Bees of the World, Charles Michener states,
“As in other aculeate Hymenoptera, the young larvae of bees have no connection between the midgut and the hindgut, so cannot defecate.”
A page on Hymenoptera can be found at https://projects.ncsu.edu/cals/course/ent425/. It states,
“The Hymenoptera is divided into two suborders: Symphyta (sawflies and horntails) have a broad junction between thorax and abdomen (and) Apocrita (ants, bees, and wasps) have a narrow junction between the thorax and abdomen.”
According to Hymenoptera of the world: An identification guide to families, “Taxonomists divide Hymenoptera into two main suborders: Symphyta, or sawflies, and Apocrita, or wasp-waisted Hymenoptera.”
Bees belong to the sub-order Apocrita.
Apocrita’s wasp waist appears to divide the thorax from the abdomen but actually the first abdominal segment is attached to the thorax. The narrow constriction allows Apocrita turn around in limited space. Attempting to avoid confusion, many authors use the term propodeum for the abdominal segment attached to the thorax and call the combination the mesosoma. The remaining abdominal segments are called the metasoma.
According to Hymenoptera of the world: An identification guide to families, “The larvae are eyeless, legless, with very small antennae or none…Apocrita larvae are found in concealed or parasitic situations.”
“Within Apocrita, two subdivisions are traditionally accepted: Parasitica (sometimes called Terebrantia) and Aculeata.”
According to California Bees and Blooms by Gordon Frankie, Robbin Thorp, Rollin Coville, and Barbara Ertter, bees, “hunting wasps,’ and ants are in the subgroup, Aculeata. Females in this group have what is called an ovipositor. Scientists believe that once, in evolutionary time, the ovipositor was used to lay eggs but has been modified into a stinger. Because they do not have an ovipositor, male bees cannot sting, although the males of some species will behave aggressively to any thing or human that enters “their territory.” (Most bees, even honey bees, are unlikely to sting someone who has not put them on the defensive, intentionally or not. Wasps are more of a danger to humans. Many bees do not have the strength to penetrate the skin of a human with their stingers.)
According to California Bees and Blooms, bees are in the superfamily, Apoidea along with the approx. 9,700 wasp species in the families Ampulicidae, Crabronidae, and Sphecidae. Adding to potential confusion, apoid wasps are referred to as spheciform wasp families. California Bees and Blooms states that, “Bees’ closest wasp relatives are in the family Crabronidae,” or according to other scientists, the subfamily of Sphecidae, Crabroninae.
In their Bees of the World, O’Toole and Raw state that bees are descendants of sphecoid wasps. Both bees and sphecoid wasps provide for their offspring and have an astonishing ability to find their way back to their nests. Both bees and wasps have solitary and highly social species with a number of intermediate levels between.
One difference between bees and wasps is that, with rare exceptions, wasps are carnivores and bees are vegetarians. Most sphecoid wasp females use their stingers to paralyze prey and bring it back to their nests as food for their larva after it emerges from the egg. Most bees bring pollen which they mix with nectar back to the nest as food for their larva after it emerges from the egg. Both sphecoid wasps and bees have some genera commonly called cuckoo wasps or bees where the females do not provide for their offspring but instead lay their eggs in the nests of other closely related species, with some notable exceptions.
In their Bees of the World, O’Toole and Raw wrote that bees and sphecoid wasps
“have the same range of nesting habits. These include burrows excavated in the ground or solid wood, the use of existing cavities and the active construction of exposed nests, using collected building materials such as mud and resin.”
Some flies, wasps, and even moths can appear similar to bees. Page three of Bee Basics: An Introduction to Our Native Bees, by Beatriz Moisset and Stephen Buchmann shows four look-alikes, in this case, an eastern yellowjacket wasp (Vespula maculifrons), a black and yellow mud dauber wasp (Sceliphron caementarium), a digger bee, in the genus Diadasia, and the nomad bee, within the genus Nomada. Pages 28 and 29 feature a few “Bee Mimics” – A bee-mimicking fly (Eupeodes sp.), another bee-mimicking (possibly bumble bee mimic) flower fly (Mallota posticata), a the drone fly (Eristalis tenax), which looks like the European honey bee (Apis mellifera), and another syrphid, or flower fly wasp mimic (Heliophilus pendulus). They write,
“Bee-flies and syrphid flies have huge eyes, very short antennae, and skinny legs when compared to bees.”
Bee Basics can be found at https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5306468.pdf.
“The Encyclopedia of Life has published Bee Observer Cards by Jessica Rykken, PhD. Card seven has photos of six look-alikes, none of them bees. They are a crabronid wasp (Cerceris sp.), a robber fly (Laphria sp.) preying on a honey bee, a hover fly often
mistaken for a honey bee (Eristalis tenax), a hover fly (Syrphus torvus),
a bee fly (Villa sp.), and a Hummingbird clearwing moth (Hemaris thysbe). It can be found at https://education.eol.org/observer/Observer-Bees-ebook-v5DL.pdf
Metallic blue and green cuckoo wasps in the family Chrysididae resemble sweat bees in the family Halictidae, but according to A Field Guide to the Insects by Donald Borror and Richard White, published in 1970, these cuckoo wasps have four or fewer abdominal segments while male bees appear to have six abdominal segments and females appear to have seven. (The first abdominal segment appears to be part of the thorax.)
Although most bees are more hairy than wasps, as California Bees and Blooms states, “Bees in the genus Hylaeus…and most cuckoo bees, such as Nomada…,are especially wasplike in appearance…..all bees have branched hairs somewhere on their bodies, whereas wasps have simple hairs.”
According to California Bees and Blooms, another difference between bees and wasps is that the segment of the leg called basitarsus is flattened in the hind legs of bees and cylindrical in wasps.
More differences are described in a document, “STINGING HYMENOPTERA: PICTORIAL KEY TO SOME COMMON UNITED STATES FAMILIES,” by Harold George Scott and Chester J. Stojanovich and the United States Centers for Disease Control and Prevention. It has black and white, technical diagrams and drawings that will help the reader distinguish between ant, wasp, and bee families. It can be found at: https://www.cdc.gov/nceh/ehs/docs/pictorial_keys/hymenoptera.pdf.
Sam Droege of the USGS Patuxent Wildlife Research Center created slide shows “25 Facts about Wild Bees in North America,” “Andrenidae Colletidae Melittidae, A guide to their identification in Eastern North America,” “Bee genera phenology 2016, and many other They can be found at: http://www.slideshare.net/sdroege.
“The Encyclopedia of Life has published Bee Observer Cards by Jessica Rykken, PhD. She uses a photo of a female Andrena commoda to introduce the names of the major bee part names. there are other photos illustrating the differences in a few bee species antennas, wings, means of pollen transport, tongue length, the character of hair, and stingers. Bee Observer Cards can be found at https://education.eol.org/observer/Observer-Bees-ebook-v5DL.pdf.
Bee Basics has wonderful illustrations by Stephen Buchmann. Using a male Anthophora centriformis as an example, it illustrates and names the major body parts on pages 4 and five. It can be found at https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5306468.pdf.
Sam Droege’s “The Very Handy Manual: How to Catch and Identify Bees and Manage a Collection” has illustrations which name more parts of a generic bee on pages 63-65. It can be found at https://www.pwrc.usgs.gov/nativebees/.
On page 17 of The Bees of the Eastern United States, Dr.Theodore Mitchell wrote, “In the classification of bees, the most significant structures are the wings and the mouthparts.” Page 17 illustrates some mouthparts of some representative bee genera. The Bees of the Eastern United States by Dr.Theodore Mitchell can be found at https://babel.hathitrust.org/cgi/pt?id=umn.31951p011131499;view=1up;seq=8
Tongue length is one of the characteristics that determines which flowers a bee can access. Certain families are called short tongued bees and others are called long tongued bees, but there are always exceptions. Researchers with Dave Goulson have found that in certain bumblebee colonies, there were both long tongued and short tongued bees because, unlike other bee genera, the size of the largest bumblebees can be ten times heavier than the smallest. Because the smaller ones stay in the nest and rear the young, most of us will never see them, when we catch them in nets or traps. Goulson speculates in his book, A Sting in the Tale, that having bees of different sizes enables the colony to survive if and when there is a shortage of one type of flower.
According to California Bees and Blooms by Gordon Frankie, Robbin Thorp, Rollin Coville, and Barbara Ertter, the shape and vein pattern in the wings of bees is important in identification to the family and species level.
Damage to wings is used in estimating the age of an individual bee specimen.
Why are there so many species of bees? Because there are so many different flowering plants. It takes time for a bee to learn how to access (and in the process pollinate) the rewards of a particular type. Not even honeybees can pollinate ever flowering plant, and many bee species only pollinate a few closely related flowering plants. The Food and Agricultural Organization of the United Nations (FAO) has created some wonderful cross section illustrations of the very different flowers of some crop plants. I urge readers/viewers look at these illustrations and imagine themselves as large or small bees and other pollinators trying to find places to land and gather pollen. Not all of these plants are pollinated by bees. In the future, I will caption some of them to describe the process of pollination and list the know pollinators. Those illustrations are part of a slide show at: at: https://www.flickr.com/photos/faooftheun/sets/72157649216707193
FAO has a webpage called “FAO’s Global Action on Pollination Services for Sustainable Agriculture-” http://www.fao.org/pollination/en/
How do scientists study bees? Of course, it depends on what is being studied. Perhaps, a place to start is by reading Pollinators in peril?
A multipark approach to evaluating bee communities in habitats vulnerable to effects from climate change by Jessica Rykken, Ann Rodman, Sam Droege, and Ralph Grundel and published by the National Park Service. It can be found at https://www.nature.nps.gov/ParkScience/Archive/PDF/Article_PDFs/ParkScience31(1)SpecialIssue2014_84-87_89-90_Rykken_et_al_3797