Bees in general and their importance as pollinators
Bees are insects belonging to the order Hymenoptera and the family Apidae. There are more than 20,000 known bee species worldwide, being essential pollinators for flora and food production. Bees pollinate approximately 75% of the crops we consume, and are fundamental to the balance of ecosystems and the global economy.
Pollination is the process by which pollen is transferred from the anthers to the stigma of a plant, allowing fertilization and reproduction. Bees fulfill this role when they visit flowers in search of nectar and pollen, which they use to feed themselves and their young. Some of the crops that rely heavily on bee pollination are almonds, blueberries, apples and tomatoes.
Threats to bees and their survival
Unfortunately, bees are currently facing numerous threats, which has led to the decline of bee populations in various regions of the world. Among the main threats are habitat loss, excessive use of pesticides, disease and climate change.
Habitat loss is one of the main causes of declining bee populations. The expansion of urban areas and intensive agriculture have led to the degradation and fragmentation of the natural habitats that bees need for foraging and reproduction. The use of pesticides in agriculture has also negatively affected bees, as they can be toxic to them and alter their behavior and learning ability.
Bees also face the threat of diseases and parasites, such as the Varroa destructor mite and the Nosema ceranae fungus, which can weaken their colonies and cause their collapse. In addition, climate change is affecting bees by altering environmental conditions and the availability of floral resources, which hinders their survival and ability to pollinate effectively.
Main bee groups and their characteristics
- Honey bees (Apis): Honeybees are probably the best known and most studied bees within the bee world. They belong to the genus Apis and are native to Eurasia and Africa. There are approximately 9 recognized species of honey bees, with the western honey bee (Apis mellifera) being the most common and widely distributed. They are known for their honey and wax production, as well as for their crucial role in plant pollination. They live in colonies composed of a queen, workers and drones. Communication among honeybees is complex and they use the buzz dance to transmit information about the location of food sources ^1^.
- Solitary bees: Unlike honey bees, solitary bees do not form colonies and, as their name implies, live and nest solitarily. It is estimated that there are more than 20,000 species of solitary bees worldwide, representing the vast majority of bee species ^2^. Examples of solitary bees include mason bees (Osmia), which build their nests using mud, and carpenter bees (Xylocopa), which nest in wood ^3^. Although they do not produce honey, solitary bees are extremely efficient pollinators and play a vital role in the pollination of wild plants and agricultural crops ^4^.
- Stingless bees (Meliponini): Stingless bees are a group of tropical and subtropical bees that belong to the tribe Meliponini and comprise about 500 species ^5^. Despite their name, some of these bees have stingers, although they are very small and cannot penetrate human skin. Stingless bees are important pollinators in their native habitats and also produce honey, although in smaller quantities than honeybees ^6^. An example of a stingless bee is the angel bee (Melipona beecheii), which is native to Central America and Mexico ^7^.
- Cuckoo bees (Nomadinae): Cuckoo bees are a subfamily of parasitic bees that includes about 3,000 species ^8^. Unlike other bees, cuckoo bees do not collect pollen or build their own nests. Instead, they lay their eggs in the nests of other bees, especially solitary bees, and their larvae feed on pollen and nectar collected by the host bees. A known example of a cuckoo bee is the red-headed cuckoo bee (Nomada ruficornis) ^9^. Despite their parasitic behavior, cuckoo bees may play a role in pollination indirectly by keeping host bee populations under control ^10^.
- Orchid bees (Euglossini): Orchid bees are a group of tropical bees found mainly in Central and South America. They belong to the Euglossini tribe and are characterized by their specialized relationship with orchids ^11^. Male orchid bees collect volatile chemicals from orchid flowers and use them to attract females during mating. This behavior is essential for pollination of many orchid species. An example of an orchid bee is the green orchid bee (Euglossa viridissima) ^12^.
- Mining bees (Andrenidae): Mining bees are a family of solitary bees that nest in the ground, excavating tunnels and chambers in the earth ^13^. There are more than 3,000 species of mining bees worldwide ^14^, and they are usually efficient pollinators of early spring flowering plants. An example of a mining bee is the spring mining bee (Andrena vaga) ^15^.
- Plumerillo bees (Dasypodaidae): Plumerillo bees, also known as scopa bees or wool bees, are a family of solitary bees characterized by their ability to collect pollen in specialized structures called scopes located on their hind legs or abdomen ^16^. There are about 3,000 species of plumerillo bees worldwide ^17^. These bees play an important role in the pollination of wild plants and crops, and some species are specialized pollinators of specific plants. An example of a feathered bee is the wool bee (Anthidium manicatum), which is known to collect wool and animal hair fibers to build its nests ^18^.
- Leafcutter bees (Megachilidae): Leafcutter bees are a family of solitary bees known for their distinctive behavior of cutting circular or semicircular pieces of leaves to build their nests ^19^. There are more than 4,000 species of leafcutter bees worldwide ^20^. Despite their leaf-cutting behavior, which can cause damage to plants, these bees are efficient pollinators and beneficial to biodiversity ^21^. An example of a leafcutter bee is the alfalfa bee (Megachile rotundata), which is an important pollinator of alfalfa and other crops ^22^.
- Sweat bees (Halictidae): Sweat bees are a family of bees that includes about 4,000 species worldwide ^23^. These bees are generally small in size and have a metallic or shiny appearance. Although some species of sweat bees are solitary, others exhibit eusocial behavior in which females cooperate in nest building and provisioning ^24^. Sweat bees are important pollinators of wild plants and crops. An example of a sweat bee is the green metallic bee (Agapostemon texanus) ^25^.
- Potter bees (Anthophoridae): Potter bees are a family of solitary bees that build mud-based nests in the form of urns or tubes ^26^. There are more than 5,000 species of potter bees worldwide ^27^. These bees are important pollinators and specialize in collecting pollen and nectar from specific plants. An example of a potter bee is Say’s potter bee (Pseudanthidium nanum), which is an efficient pollinator of tubular flowers ^28^.
In summary, there is a great diversity of bee groups with unique characteristics and behaviors. From honeybees to solitary bees to stingless bees to cuckoo bees, each group plays a vital role in pollination and maintaining biodiversity. Understanding and protecting these different bee species is essential to ensure the health of our ecosystems and global food security.
Did you know that...? Curiosities about bees
- Bees have an impressive impressive memory and can recognize human faces, learn to associate colors with food sources, and communicate the location of flowers to their mates through a dance called the bee dance.
- Some bees, such as the
(Euglossini), specialize in pollinating a single plant species. These bees collect fragrances from orchids to attract females during mating, and in doing so, pollinate the flowers.
- Bees can count up to
count to four
and have the ability to solve simple mathematical problems, such as addition and subtraction.
- Drones, the male honey bees, have no stinger and cannot sting. Its only function in the colony is to
with the queen.
- Bees can understand
understand the concept of zero
making them one of the few known non-human animals capable of understanding this abstract concept.
- Honey bees
honey bees sleep
and have sleep cycles similar to humans, sleeping between 5 and 8 hours a day. Worker bees sleep inside the hive, while guard bees sleep near the entrance to protect the hive from intruders.
- In some regions of Asia, giant bees
giant honey bees
(Apis dorsata) nest in cliffs and tall trees, leading honey collectors to climb dizzying heights to obtain their honey and wax. These bees produce honey with medicinal properties, which is highly valued in some cultures.
By learning more about bees and their fascinating characteristics, we can appreciate their importance as pollinators and understand the need to protect them. Ensuring the conservation of bees is essential to maintain biodiversity and guarantee food production worldwide.