Dominance of African racial ancestry in honey bee colonies of Mexico 30 years after the migration of hybrids from South America.

The Africanized honey bee, a hybrid of from Africa with European subspecies, has been considered an invasive species and a problem for beekeeping. Africanized bees arrived in Mexico in 1986, 30 years after their accidental release in Brazil. Although government programs were implemented for its eradication, Africanized populations persist in Mexico, but precise information on the patterns of genetic introgression and racial ancestry is scarce.

Effects of floral resources on honey bee populations in Mexico: Using dietary metabarcoding to examine landscape quality in agroecosystems.

The decline of honey bee populations significantly impacts the human food supply due to poor pollination and yield decreases of essential crop species. Given the reduction of pollinators, research into critical landscape components, such as floral resource availability and land use change, might provide valuable information about the nutritional status and health of honey bee colonies. To address this issue, we examine the effects of landscape factors like agricultural area, urban area, and climatic factors, including maximum temperature, minimum temperature, relative humidity, and precipitation, on honey bee hive populations and nutritional health of 326 honey bee colonies across varying landscapes in Mexico.

Long-term spatiotemporal patterns in the number of colonies and honey production in Mexico.

Honey bee decline is currently one of the world's most serious environmental issues, and scientists, governments, and producers have generated interest in understanding its causes and consequences in honey production and food supply. Mexico is one of the world's top honey producers, however, the honey bee population's status has not been documented to date. Based on 32 years of data from beekeeping, we make a country-level assessment of honey bee colony trends in Mexico.

Effect of juvenile hormone on phenoloxidase and hemocyte number: The role of age, sex, and immune challenge.

Hormones are key factors in determining the response of organisms to their environment. For example, the juvenile hormone (JH) coordinates the insects' development, reproduction, and survival. However, it is still unclear how the impact of juvenile hormone on insect immunity varies depending on the sex and reproductive state of the individual, as well as the type of the immune challenge (i.

The honey bees immune memory.

Invertebrates' immune priming or innate immune memory is an analogous response to the vertebrates' adaptive memory. We investigated if honey bees have immune memory. We compared survival and immune response between bees that were: 1) manipulated (Naïve), 2) challenged twice with the same pathogen Escherichia coli (Memory), 3) challenged twice with different pathogens (Staphylococcus aureus versus E.

The costs of the immune memory within generations.

Immune response is evolutionary costly, but it is not clear whether these costs affect energetic expenditure (short-term cost), growth (medium-term cost), or reproduction (long-term cost). We tested the costs of immune memory in Tenebrio molitor against Metarhizium brunneum. To do this, we used two groups of T.

Costs and benefits of vertical and horizontal transmission of dengue virus.

Parasites can be transmitted vertically and/or horizontally, but the costs or benefits for the host of infection have only been tested after horizontal transmission. Here, we report for the first time, to our knowledge, the survival, reproduction and infection of Aedes aegypti during vertical and horizontal transmission of dengue virus 2 (DENV-2). Females infected horizontally produced more eggs, with a sex ratio skewed towards males, compared with uninfected controls.

Sexual dimorphism in immune response: testing the hypothesis in an insect species with two male morphs.

It has been proposed that given that males should invest in sexual traits at the expense of their investment in immune response, females are better immunocompetent than males. Typically, this idea has been tested in monomorphic species, but rarely has been evaluated in polymorphic male species. We used Paraphlebia zoe, a damselfly with two male morphs: the black-winged morph (Black-W) develop black spots as sexual traits and the hyaline-winged morph (Hyaline-W) resembles a female in size and wings color.