- Author: Kathy Keatley Garvey
The blood-sucking insect, which transmits the parasite that causes human and animal trypanosomiasis, has wreaked havoc in African countries.
It's distinguished from other Diptera by unique adaptations, "including lactation and the birthing of live young," says medical entomologist-geneticist Geoffrey Attardo, assistant professor, UC Davis Department of Entomology and Nematology.
Mark your calendar.
The UC Davis Department of Animal Science is hosting his seminar, “Tsetse Fly Reproduction: Exploration of the Unique Reproductive Adaptations of a Neglected Disease Vector” at 12:10 p.m., Monday, Oct. 7 in the Weir Room, 2154 Meyer Hall.
"Tsetse flies function as the sole vectors of human and animal Trypanosomiasis in sub-Saharan Africa," Attardo says in his abstract. "In addition to their role as disease vectors, tsetse flies distinguish themselves from other flies in terms of their amazing physiological adaptations. Of these adaptations, the reproductive biology/physiology of these flies stands out as one of the most dramatic."
"Female tsetse flies carry their young in an adapted uterus for the entirety of their immature development and provide their complete nutritional requirements via the synthesis and secretion of a milk like substance. Tsetse milk is derived of roughly 50 percent lipids and 50 percent proteins. Tsetse milk proteins are coded for by repurposed genes and by genes specific to tsetse flies. These genes are regulated in tight correlation with the female's pregnancy cycle. In addition, tsetse flies have established an obligate relationship with the bacterial symbiont Wigglesworthia glossinidius. This symbiont is required for lactation and larval development. Metabolic analysis of tsetse flies lacking this symbiont reveals a tightly integrated relationship between these organisms. This relationship is required for the metabolism of blood, production of essential micronutrients and synthesis/secretion of lipids essential for milk production.”
Attardo led landmark research published Sept. 2 in the journal Genome Biology that provides new insight into the genomics of the tsetse fly. The researchers compared and analyzed the genomes of six species of tsetse flies. Their research could lead to better insights into disease prevention and control.
“It was a behemoth project, spanning six to seven years,” said Attardo. “This project represents the combined efforts of a consortium of 56 researchers throughout the United States, Europe, Africa and China.” (See news story.)
In 1995, the World Health Organization (WHO) estimated that 60 million people were at risk of sleeping sickness, with an estimated 300,000 new cases per year in Africa, and fewer than 30,000 cases diagnosed and treated. Due to increased control, only 3796 cases were reported in 2014, with less than 15,000 estimated cases, according to WHO statistics.
WHO says that the parasitic disease “mostly affects poor populations living in remote rural areas of Africa. Untreated, it is usually fatal. Travelers also risk becoming infected if they venture through regions where the insect is common. Generally, the disease is not found in urban areas, although cases have been reported in suburban areas of big cities in some disease endemic countries.”
- Author: Kathy Keatley Garvey
Those are some of the questions that Wolf asks. "We aim to find some of the molecular and neural circuit mechanisms that govern adult behavior in the fruit fly Drosophila."
Wolf, who holds a doctorate in molecular and cell biology from UC Berkeley, will speak on "Drinking Drosophila and Drunk Drosophila: Genes and Circuits for Simple Behaviors" at the next UC Davis Department of Entomology and Nematology seminar, set for 4:10 p.m., Wednesday, Oct. 31 in 122 Briggs Hall.
"How is motivation coded in a small brain?" Wolf asks. "How does a natural motivation like a thirst differ from drug-seeking in addiction? We use circuit mapping, genetics and behavior in Drosophila melanogaster to find out internal states combine with environmental information to select behavioral programs and suppress others."
Molecular geneticist Joanna Chiu, associate professor and vice chair of the UC Davis Department of Entomology and Nematology, will introduce the speaker and serve as the host. Medical entomologist Geoffrey Attardo coordinates the fall seminars.
The Drosophila fly nervous system is remarkable. Wolf says it's "a million-fold simpler than ours, yet flies are capable of carrying out remarkably sophisticated tasks that are modified by past experience and internal states. However, the biological bases for even simple behavioral actions that serve as models for more complex tasks remain mysterious. Understanding how circuits function in a model organism where rapid progress can be made with highly sophisticated tools is likely to provide insight into how more complicated brains work."
No wonder that Drosophila melanogaster, is a favorite model organism among biomedical researchers.
"There are many technical advantages of using Drosophila over vertebrate models; they are easy and inexpensive to culture in laboratory conditions, have a much shorter life cycle, they produce large numbers of externally laid embryos and they can be genetically modified in numerous ways," according to Barbara Jennings in ScienceDirect.com. "Research using Drosophila has made key advances in our understanding of regenerative biology and will no doubt contribute to the future of regenerative medicine in many different ways."
"Over the past four decades," Jennings points out, "Drosophila has become a predominant model used to understand how genes direct the development of an embryo from a single cell to a mature multicellular organism." Indeed, numerous scientists have won Nobel Prizes for their research on the fruit fly.
What does the scientific name, Drosophila melanogaster, mean? Drosophila means "dew lover" and melanogaster means "dark gut."
- Author: Kathy Keatley Garvey
Do you know where your nematodes are? If you're a grower, you should.
"To make informed management decisions and ensure that environmentally damaging soil fumigants are applied only when and where needed, growers need to know precisely the density and distribution of pest nematodes," says nematologist Amanda Hodson, a professional researcher in the UC Davis Department of Entomology and Nematology who will present a departmental seminar at 4:10 p.m., Wednesday, Jan. 31 in 122 Briggs Hall.
Hodson, who will deliver the hourlong seminar on "Molecular Detection and Integrated Management of Plant Parasitic Nematodes," studies the interrelationships between nematode pests, ecosystem functioning and management decisions.
"Molecular methods overcome some of the drawbacks of the labor and time intensive process of nematode detection," she says. "Our analysis has established the accuracy of real time PCR (qPCR) primers which accurately differentiate and quantify several pest nematodes from other nematodes in the soil including lesion nematode (Pratylenchus vulnus), ring nematode (Mesocriconema xenoplax) and two separate groups of root knot nematodes (Meloidogyne spp.). Integrated management of these soil pests requires better understanding of the interactions between nematode pest suppression, soil food webs, management tactics, crop productivity, and soil health. Our experiments link managing for nematode pest suppression with other desired ecological outcomes such as increased soil organic matter and nutrient cycling in cropping systems such as almonds, tomatoes and carrots."
Hodson's research integrates plant and root biology with the fields of entomology, nematology, acarology and biogeochemistry. She completed her doctorate in entomology at UC Davis in 2010 on the ecological effects of a biological control agent in pistachio orchards, finding that the entomopathogenic nematode, Steinernema carpocapsae, caused temporary changes in native soil food webs. Following up on these results in the laboratory, she found that the European earwig (Forficula auricularia) could serve as a novel host for the nematode. This susceptibility depended on host body size with significantly higher mortality rates seen in larger earwigs.
The departmental seminars (see schedule) are open to all interested persons. Seminar coordinators are assistant professor Rachel Vannette, Extension apiculturist Elina Lastro Niño and doctoral student Brendon Boudinot of the Phil Ward lab.
- Author: Kathy Keatley Garvey
Borowiec, who received his doctorate in entomology in June from the University of California, Davis, studying with major professor Phil Ward, will speak on "Genomic Data and the Tree of Life: Known Knowns, Known Unknowns, and Unknown Unknowns of Army Ant Evolution" at his exit seminar.
Set from 4:10 to 5 p.m. on Wednesday, Oct. 26 in 122 Briggs Hall, Kleiber Hall Drive, the seminar will be hosted by the UC Davis Department of Entomology and Nematology. Plans call for video-recording the seminar for later posting on UCTV.
"I got interested in ants after reading E. O. Wilson's autobiography 'Naturalist' as a freshman in college," Borowiec related. "I'm fascinated by the diversity of form and function in ants, that is, by the various ways they make a living and the incredible variation of their morphologies."
Harvard University professor Wilson, one of the world's most distinguished scientists, is two-time recipient of the Pulitzer Prize. (See his Ted talks.)
"Ants are the world's most successful eusocial organisms," said Borowiec, whose research interests include phylogeny, taxonomy, biogeography, and natural history of ants. "Long history, high species diversity, and extreme variety of life histories make them an excellent group in which many evolutionary questions can be addressed."
"My dissertation research at UC Davis focused on building a taxonomic and phylogenetic framework for the research on army ant evolution," said Borowiec, who received his master's degree in 2009 from the Department of Biodiversity and Evolutionary Taxonomy, University of Wroclaw, Poland. "Although army ants include very charismatic species, they belong to a larger group, the subfamily Dorylinae. In addition to the army ants, dorylines comprise many cryptic ants whose biology and even taxonomy have been neglected. Partly as a result of this, even phylogenetic relationships of the army ants are not well-understood. The first step to advancing evolutionary research in the group was thus to examine the morphological diversity within this lineage. This resulted in a generic revision of the subfamily, published open-access in ZooKeys. Expertise gained during this work allowed me to design robust taxon sampling for a phylogeny of the dorylines based on next-generation sequencing data (ultraconserved elements or UCEs), currently in preparation."
Borowiec is now a postdoc in the lab of evolutionary biologist Christian Rabeling of Rochester, N.Y. who works on ants. In January the lab will be moving to Tempe, Ariz.
Myrmecologist Marek Borowiec would certainly agree with E.O. Wilson's noted quotes about ants:
- "Ants have the most complicated social organization on earth next to humans."
- "Ants are the dominant insects of the world, and they've had a great impact on habitats almost all over the land surface of the world for more than 50 million years."
- "When you have seen one ant, one bird, one tree, you have not seen them all."
- Author: Kathy Keatley Garvey
John "Jack" Longino knows his ants.
Longino, known by his students as "The Astonishing Ant Man," will present a seminar to the UC Davis Department of Entomology and Nematology from 12:10 to 1 p.m., Wednesday, May 27 in 122 Briggs Hall, Kleiber Hall Drive.
His topic: "Project ADMAC or Ant Diversity of the Mesoamerican Corridor."
Longino, who received his bachelor's degree in zoology, with distinction, in 1978 from Duke University, and his doctorate in zoology in 1984 from the University of Texas, Austin, traces his fascination with insects back to his childhood. He developed an interest in ecology and the desire to explain patterns of diversity, so "I settled on ants as an ecologically dominant group of insects worthy of study."
"As it became clear that I was living during a time of enormous biotic change caused by human activities, I developed a strong conviction that it was important not only to understand patterns of diversity but to document it in detail for this time in history. I divide my time between two research fields: taxonomy and ecology. On the taxonomy side, I have coordinated large-scale inventories of Neotropical insect biodiversity, I discover and describe new species of ants, and I further refine our understanding of species ranges and morphological variability. I make use of advanced imaging technology, specimen-level databases, and Web-dissemination to make biodiversity data available to the widest audiences."
"On the ecology side, I use quantitative inventory techniques that allow analysis of diversity patterns. I am interested in how species are distributed on tropical mountainsides, what ecological factors explain the elevational range limits of species, and how species might respond to climate change."
Ant specialist Phil Ward, UC Davis professor of entomology (and also known as "the ultimate ant man") will introduce and host Longino.
What is the MesoAmerican corridor? It's a zone of complex tectonic history, episodic biotic interchange between large continents, and frequent mountain-building," Longino says. "Ants blanket this landscape, forming a tapestry of fine-scale habitat specialization and geographic replacement. Many taxonomists have contributed to the description of species in the region and this fundamental 'biodiversity mapping' continues apace. Project ADMAC (Ant Diversity of the MesoAmerican Corridor) combines morphological analysis with large-scale DNA sequencing (targeted enrichment of Ultra-Conserved Elements) to reveal the evolutionary history and geographic structure of ant species in MesoAmerica."
"Ants show very strong patterns of elevational specialization and geographic turnover, and Project ADMAC will address questions of (1) how and when montane species evolve, (2) the effects of differing mountain ages on communities, (3) the impact of lowland barriers on montane ant dispersal, and (4) whether ants experienced a major biotic interchange on the closure of the Panamanian isthmus."
National Public Radio interviewed Longino in August of 2013 on his research. He told NPR he started out collecting stamps in his childhood, but that bored him. He decided to "get small."
"If you're shopping for a home entertainment system," he says, "you can't do better than a good dissecting microscope," he said. At the time of the NPR interview, Longino had just published two papers describing 33 new species of ants, bringing his personal "new species" total to 131, NPR reported. In the article, Longino described himself as "average" among entomologists, pointing out that some entomologists have described thousands of new species.
So, if you're like Longino, if you had a choice between a home entertainment system and a good dissecting microscope, the winner--hands down--would be the dissecting microscope.
And if you want to know about ants, you can download Dr. Eleanor's Book of Common Ants for free at http://ants.yourwildlife.org/dr-eleanors-book-of-common-ants/. It's the work of science writer Eleanor Spicer Rice, noted insect photographer Alex Wild, and designer Neil McCoy.
Be sure to check out Alex Wild's Myrmecos blog at http://www.myrmecos.net/ for amazing ant photos and educational information. He holds a doctorate in entomology from UC Davis (major professor Phil Ward) and is now curator of Entomology in the College of Natural Sciences, University of Austin--the university where Longino received his doctorate.
All in the family...the ant family...Formicidae.