Carolina Reisenman, Associate Researcher

Closed (1) Taste adaptations to host specialization in specialist species of Drosophila.

Closed. This professor is continuing with Fall 2021 apprentices on this project; no new apprentices needed for Spring 2022.

Chemosensory-driven hostplant specialization is a major force mediating insect ecological adaptation and speciation. In particular, the role of the olfactory system in mediating host specialization is well understood in many insect species, but that of the taste sensory system has been much less studied, despite its primordial role in enabling organisms to recognize food.
Drosophila sechellia is a fruit fly species endemic to the Seychelles islands in the Indian Ocean which exclusively feeds and oviposits on Morinda citrifolia. This fruit is harmless to D. sechellia but toxic to many other Drosophilidae, including the closely related generalist species D. simulans and D. melanogaster. While several olfactory adaptations mediating the preference of D. sechellia for its host have been uncovered, the role of the taste system in this process, although suspected, is not completely understood. Moreover, this fly species lost not only many olfactory receptors, but also many gustatory “bitter” receptors. The goal of this broad ongoing project is to investigate the taste and feeding responses of D. sechellia, and compare them with those of its close generalist relatives.



This project uses behavioral methods to study fly taste and feeding responses. The student/s will learn how to rear and sort flies, learn fly genetics, fly husbandry, laboratory methods, conduct behavioral experiments, collect and analyze data, and chemical ecology methods as necessary. They will also use tools readily available to investigate the role of chemosensory proteins in host specialization, such as D. melanogaster mutants, lines in which specific neuronal types can be activated or suppressed, etc. The experiments will be conducted in the laboratory of Dr. Kristin Scott, under the supervision and direction of Dr. Carolina Reisenman.

Day-to-day supervisor for this project: Carolina Reisenman, Staff Researcher

Qualifications: Qualifications: Introductory biology; general chemistry highly desirable. The student/s should be curious, highly motivated and have a responsible attitude in the lab. The student is also expected to be interested in reading research articles, maintain a well-organized research notebook and write down protocols. A positive attitude is a must! The student should be available 8-10 hours during weekdays, and 2-3 hours (or more if case of scheduling conflicts during weekdays) during weekends. Please refrain from applying if you can't commit to at least 2-3 hours of work during weekends.

Weekly Hours: 9-11 hrs

Related website: http://mcb.berkeley.edu/labs/scott/
Related website: http://mcb.berkeley.edu/labs/scott/reisenman/

Closed (2) Neural circuits mediating feeding enhancement by odors in Drosophila melanogaster

Closed. This professor is continuing with Fall 2021 apprentices on this project; no new apprentices needed for Spring 2022.

Insects use multiple sensory modalities when searching for and accepting a food source, in particular odor and taste cues. Food-derived odorants are generally involved in mediating long-and short-range attraction. Taste cues, on the other hand, act directly by contact with the food source, promoting the ingestion of nutritious food and the avoidance of toxic substances. We have previously shown that the presence of both single food-derived odorants and complex odor mixtures enhanced consumption of an appetitive food in the fruit fly Drosophila melanogaster. D. melanogaster constitutes an excellent model system to study chemosensory integration, as much is known about the organization of its taste and olfactory systems, and of the behavioral programs and neuronal mechanisms controlling feeding decisions. This fly species is also an excellent model system to investigate the neural mechanism controlling behavior, as many powerful genetic tools are readily available for the manipulation of specific neurons.

In this project, the student/s will conduct behavioral experimental to investigate 1) which olfactory receptor protein/s are involved in the enhancement of feeding by food-derived volatiles and 2) whether higher brain centers mediating learning and memory are necessary for mediating this enhancement effect.

This project uses behavioral methods to study food consumption. The student/s will learn how to rear and sort flies, basic fly genetics, fly husbandry, laboratory methods, learn to work with odors, conduct behavioral experiments, collect and analyze data, use lines in which specific neuronal types can be activated or suppressed, etc.

The experiments will be conducted in the laboratory of Dr. Kristin Scott, under the supervision and direction of Dr. Carolina Reisenman.

The student/s should be available to work 2-3 hours during weekends (or more if there are schedule conflicts during the week). Please refrain from applying if you can't commit to at least 2-3 hours of work during weekends.


This project uses behavioral methods to study fly olfactory and taste behavioral responses. The student/s will learn how to rear and sort flies, learn fly genetics, fly husbandry, laboratory methods, conduct behavioral experiments, collect and analyze data, and chemical ecology methods as necessary. They will also use tools readily available to investigate the role of specific chemosensory proteins in this process, such as D. melanogaster mutants, lines in which specific neuronal types can be activated or suppressed, etc. The experiments will be conducted in the laboratory of Dr. Kristin Scott, under the supervision and direction of Dr. Carolina Reisenman.



Day-to-day supervisor for this project: Carolina Reisenman, Staff Researcher

Qualifications: General biology is required, general chemistry highly desirable. We are looking for one or more students who are curious, detail-oriented, punctual, and can collect/record data in an organized fashion, and is interested in reading relevant literature. The student will gain hands on experience being a scientist in a lab. Commitment and a positive attitude are a must! The student should be available 8-10 hours during weekdays, and 2-3 hours (or more if case of scheduling conflicts during weekdays) during weekends.

Weekly Hours: 9-11 hrs

Related website: http://mcb.berkeley.edu/labs/scott/
Related website: http://mcb.berkeley.edu/labs/scott/reisenman/

Closed (3) Behavioral mechanisms underlying host specialization in specialist herbivorous flies.

Closed. This professor is continuing with Fall 2021 apprentices on this project; no new apprentices needed for Spring 2022.

Herbivory is a major evolutionary achievement in insects, with nearly half of all existing species feeding on living plants. While many herbivorous insects feed in many plant species, most herbivorous are specialists, with larvae feeding and adults ovipositing on a small number of closely related plant species. Transitions from a generalist lifestyle to specialization are common; in many cases morphological and physiological adaptations accompany host plant specialization, including detoxification mechanisms against plant defenses and sensory specializations for the detection of host-derived chemical (olfactory and taste) cues. In particular, the importance of the chemosensory system in host plant choice, along with the fact that specialists outnumber generalists, suggests that the evolution of insect– plant interactions is based on changes within the insect nervous system. Of particular interest among specialist herbivorous insects is the fly Scaptomiza flava, a species which is nested within Drosophila and is specialized in mustard plants such as broccoli, cabbage, radishes, arugula, etc. While this fly feeds on and needs plant tissue to complete its developmental cycle (i.e., it is a truly herbivorous insect), most of its close relatives are microbe-feeding and use decomposing material. Thus, this constitutes a great system to study the evolutionary transitions that allowed S. flava to use these plants, while at the same time help uncovering the general mechanisms that allowed insect shifts in dietary lifestyle.
The behaviors of S. flava and its close relatives, and their relevance for niche exploitation, begun to be uncovered only recently. Students will join current projects in the laboratory of Dr. Noah Whiteman involving chemosensory adaptations in diverse behaviors such feeding, oviposition, mate-choice, water-sensing, and adaptations of the visual system to host detection.

The students will learn to rear flies and their host plants, fly husbandry, laboratory methods, chemical ecology methods, help conducting ongoing behavioral tests of olfactory behavior, develop new methods for quantification of various behaviors, and collect and analyze data. Due to the comparative nature of this work, students will work with different fruit fly species in addition to S. flava.

Research for this project will be conducted in the laboratories of Drs. Noah Whiteman (Integrative Biology) and Kristin Scott (Molecular and Cell Biology).


This project uses behavioral methods to study chemosensory adaptations to herbivory across closely related species of drosophilid flies. The student/s will learn how to rear and sort flies, learn fly genetics, fly husbandry, laboratory methods, conduct behavioral experiments, rear plants, collect and analyze data, and chemical ecology methods as necessary. They will also use tools readily available to investigate the role of specific chemosensory proteins in this process. The experiments will be conducted in the laboratory of Dr. Kristin Scott, under the supervision and direction of Dr. Carolina Reisenman.




Day-to-day supervisor for this project: Drs. Carolina Reisenman and Teruyuki Matsunaga, Staff Researcher

Qualifications: General biology is required, general chemistry highly desirable, ecology/evolution preferable. We are looking for one or more students who are curious, detail-oriented, punctual, and can collect/record data in an organized fashion, and is interested in reading relevant literature. The student will gain hands on experience being a scientist in a lab. Commitment and a positive attitude are a must! The student should be available 8-10 hours during weekdays, and 2-3 hours (or more if case of scheduling conflicts during weekdays) during weekends. Please refrain from applying if you can't commit to at least 2-3 hours of work during weekends.

Weekly Hours: 9-11 hrs

Related website: http://www.noahwhiteman.org/
Related website: http://mcb.berkeley.edu/labs/scott/reisenman/