Ecological theory holds that plant-hungry creatures help shape ecosystems by mowing down dominant plants that might smother other plants, thus enhancing biodiversity — but only if the area is lush. A new study co-authored by University of Florida biologist Todd Palmer in today’s edition of Nature Ecology & Evolution shows that this widely-believed theory might not be entirely true.

The researchers synthesized data from more than 250 vegetation-heavy areas, examining areas both grazed and non-grazed by large herbivores. “Large herbivore populations are in decline in ecosystems across the globe, and so understanding how these declines are likely to affect biodiversity is really important,” said Palmer. This paper takes some important steps in clarifying where and when we might expect these declines to have big consequences for the surrounding ecological communities.

By comparing data on the effects of herbivores on plant communities across a wide range of productivity, the researchers found that the effects of grazing animals on biodiversity could be predicted by understanding the impact that herbivory has on plant dominance. When grazing animals reduced dominance by feeding on abundant species that appealed to their tastes, the grazers increased biodiversity by freeing up resources for other, less dominant plant species. However, in areas where the most abundant plant species are resistant to grazing, herbivores increased dominance by feeding on the rare and tasty species, thereby reducing biodiversity.

“There’s been a lot of confusion out there in the literature trying to understand why herbivores sometimes increase and sometimes decrease biodiversity, and this paper really nails why they have different effects under different circumstances,” said Palmer.

These results suggest that management of dominance, not of grazing activity per se, is key to conserving biodiversity.

Post-Traumatic Stress Disorder (PTSD) affects 3.5 percent of the U.S. population (compared to 1 percent elsewhere), and the majority of PTSD patients experience substance use disorder. In particular, PSTD and cocaine use disorder tend to be comorbid, with significant overlap between the two disorders. The development of potential medications to treat individuals suffering PTSD, and others suffering PTSD who also are abusing drugs, is hindered by a lack of animal models to study the brain changes caused by PTSD alone and in combination with drug abuse.

Lori Knackstedt, UF professor of psychology and a drug abuse expert at the University of Florida, is lead author on a new study showing a novel animal model with which to study comorbid PTSD and addiction. Comorbidity is the condition of one person suffering two simultaneous diseases. Using this newly developed model, researchers could identify specific gene that can be targeted for treatment. Their work was recently published in the journal Translational Psychiatry.

PTSD tends to occur from a single traumatic event, but not all individuals who experience trauma develop PTSD. Of those that do, anxiety symptoms tend to be long-lasting and interfere with everyday life. Animal models of PTSD currently in use typically study all animals that are exposed to the stressor. This new approach, uses a single exposure to predator scent and examines long term anxiety symptoms; identifying only a small populations of rodents that exhibit such long-lasting symptoms. This new model then evaluates drug-seeking behavior and relapse in such stress “susceptible” rats, finding major differences in brain gene expression and stress hormone levels between the anxious rats and resilient rats.

“We were inspired to start this project because the vast majority (more than 95 percent) of animal studies investigating comorbid PTSD and addiction do not separate out the PTSD-like rats or mice from resilient rats or mice,” said Knackstedt. “We found, that like humans, not all rats develop long-term anxiety after a stressor.”

The researchers hypothesized that stress-susceptible individuals would exhibit a greater escalation of cocaine intake relative to stress-resilient individuals than those in the control group. Based on previous work by Knackstedt and her team showing that the antibiotic Ceftriaxone (Cef) is able to reduce recurring impulses to seek cocaine, the team administered Cef to understand its potential role in treating PTSD comorbid with cocaine addiction. Cocaine inhibits, while Ceftriaxone encourages, the expression of two proteins, xCT and GLT-1, in the nucleus accumbens, the reward center of the brain. These proteins control glutamate homeostasis and are important regulators of cocaine relapse. Ceftriaxone appears to increase reuptake of glutamate, a neurotransmitter that regulates dopamine, the crux of the reward system.

In the present research, Cef prevented drug-seeking in stress-resilient and control individuals, but only attenuated it in stress-susceptible individuals. The researchers found that neuroplasticity is key to stress resilience and is mediated by the expression of the genes mGlu5 and CBI in the amygdala, which controls fear, and mGlu5 in the medial prefrontal cortex, which regulates short-term memory. Targeting these genes could improve treatment for individuals with PTSD.

For stress-susceptible individuals, “We find that re-exposure to the trauma environment without the trauma present, akin to exposure therapy in humans, is a key mediator of treatment,” the researchers said in a statement.

“Now that we have an animal model that closely mimics the symptoms of patients who have both PTSD and cocaine use disorder, such as anxiety that will not end and persistent drug seeking, we and other scientists can use a model to determine the underlying changes in the brain and design better treatments,” said Knackstedt.

Several of the African American Studies core faculty members, affiliate faculty members, and advisory board members are members of research teams that have been awarded Intersections Grants from the Mellon Foundation (organized by the Center for the Humanities and Public Sphere).  See the information below and information about each of the four grants

The African American Studies faculty, affiliates, and advisory board members involved in these grants are:

Tanya Saunders, Manoucheka Celeste, Bryce Henson, Ben Hebblethwaite, Paul Ortiz, Nick Vargas, Chris Busey, Agnes Leslie, Stephanie Birch, Katheryn Russell-Brown, Lauren Pearlman, and Sharon Austin.  Sophia Acord and Barbara Mennel of the Center for the Humanities also assisted with these grants.

Dr. Manoucheka Celeste, Assistant Professor of African American Studies and Gender, Women’s Studies, and Sexualities Research, recently won the Diamond Anniversary Book Award from the National Communication Association for her book, Race, Gender, and Citizenship in the African Diaspora: Travelling Blackness (Routledge 2017). This Award is given to “the most outstanding scholarly book published during the previous two years.”  For more information, see 2018 NCA Award Winners.  This book also won the 2017 National Communication Association Outstanding Book Award from the African American Communication & Culture Division and the Black Caucus.  Congratulations Dr. Celeste!

During the 2018 spring break in March, Dr. Sharon Austin accompanied 13 students to Paris for the African Americans in Paris class.  This was the fifth consecutive year the class was offered.  The students watched online lectures, read materials, completed papers, and took an exam before traveling to France.  While there, they listened to lectures and visited several historic sites of significance to African American ex-patriates who fled the U.S. and lived in France to escape American discrimination and injustices.  The students visited the suburban home of the late entertainer Josephine Baker, Versailles Palace, and the Louvre Museum.  They also took a cruise of the River Seine and visited the Eiffel Tower as well as several of the cities’ neighborhoods such as Montmarte and Goutte D’Or.  Many visited Amsterdam, Barcelona, London, and Rome on their free day.  The course will be offered every year during spring break. For more information,visit our website, YouTube page, or contact Dr. Austin at polssdw@ufl.edu.

A picture of Dr. Patricia Hillard with his students

In the fall of 2017, Dr. Patricia Hilliard-Nunn took three African American Studies students, Kayla O’Neal, DeAunte Fox, and Syleena Powell, to the Annual Meeting of the Association of African American Life and History (ASALH) Conference in Cincinnati, Ohio to present their research on a panel entitled “The Implications of Gender and Race in Three Dimensions.”  The title of O’Neal’s paper was “Black Children and Zero Tolerance Policies in Florida’s Schools.  Fox’s paper was entitled “A Content Analysis of Black Male Relationships in the films Get Out, Moonlight, and Fences.”  Finally, the title of Powell’s paper was “The Strong Black Woman Stereotype and Black Female Coping Strategies.”

In March 2018, Tiara Telfair and Jasmyn Sullivan presented research at the National Conference of Black Political Scientists Meeting in Chicago, Illinois.

Dr. Sharon Austin’s third book, The Caribbeanization of Black Politics: Race, Group Consciousness, and Political Participation in America, was published by SUNY, Albany Press in March 2018.  She has also been promoted to the rank of full professor.  You can access some of her articles for The Conversation at the links below.  Congratulations Dr. Austin!

 

Dr. Vincent Adejumo won a Teacher of the Year Award from the College of Liberal Arts and Sciences during the spring 2018 semester. Dr. Adejumo has been a Lecturer in the UF African American Studies Program since 2015 and had served as a graduate teaching assistant since 2011. He teaches a number of courses including the online version of Introduction to African American Studies, Black Masculinity, Black Wall Street, and The Wire. Congratulations Dr. Vince!

Dr. Vincent Adejumo Receoves Teacher of the Year Award

Dr. Vincent Adejumo won a Teacher of the Year Award from the College of Liberal Arts and Sciences during the spring 2018 semester.  Dr. Adejumo has been a Lecturer in the UF African American Studies Program since 2015 and had served as a graduate teaching assistant since 2011.  He teaches a number of courses including the online version of Introduction to African American Studies, Black Masculinity, Black Wall Street, and The Wire. Congratulations Dr. Vince!
A picture of Dr. Vincent Adejumo receiving award

Dr. Sharon Austin’s Promotion to Full Professor

Dr. Sharon Austin’s third book, The Caribbeanization of Black Politics: Race, Group Consciousness, and Political Participation in America, was published by SUNY, Albany Press in March 2018.  She has also been promoted to the rank of full professor.  You can access some of her articles for The Conversation at the links below.  Congratulations Dr. Austin!
Could Andrew Gillum be the next governor of Florida?
why Florida democrats can’t count on the so called black vote?
How Stacey Abrams black girl magic turned Georgia bit more blue?

A picture of Dr. Sharon Austin

AFA Students Present Research at Academic Conferences

In  the fall of 2017, Dr. Patricia Hilliard-Nunn took three African American Studies students, – Kayla O’Neal, DeAunte Fox, and Syleena Powell—to the Annual Meeting of the Association of African American Life and History (ASALH) Conference in Cincinnati, Ohio to present their research on a panel entitled “The Implications of Gender and Race in Three Dimensions”.  The title of O’Neal’s paper was “Black Children and Zero Tolerance Policies in Florida’s Schools.  Fox’s paper was entitled “A Content Analysis of Black Male Relationships in the films Get Out, Moonlight, and Fences.”  Finally, the title of Powell’s paper was “The Strong Black Woman Stereotype and Black Female Coping Strategies.”

A picture of Dr. Patricia Hillard with his students
In March 2018, Tiara Telfair and Jasmyn Sullivan presented research at the National Conference of Black Political Scientists Meeting in Chicago, Illinois.  Pictured below in the photo on the left are Dr. Robert Brown of Spelman College, Tiara Telfair, Allison Austin, and Dr. Sharon Austin.  Pictured in the photo on the right are Dr. Robert Brown, Dr. Sharon Austin, Allison Austin, Jasmyn Sullivan, and Tiara Telfair.

A picture of Tiara Telfair and Jasmyn Sullivan with students

African Americans in Paris Spring Break Class

During the 2018 spring break in March, Dr. Sharon Austin accompanied 13 students to Paris for the African Americans in Paris class.  This was the fifth consecutive year the class was offered.  The students watched online lectures, read materials, completed papers, and took an exam before traveling to France.  While there, they listened to lectures and visited several historic sites of significance to African American ex-patriates who fled the U.S. and lived in France to escape American discrimination and injustices.  The students visited the suburban home of the late entertainer Josephine Baker, Versailles Palace, and the Louvre Museum.  They also took a cruise of the River Seine and visited the Eiffel Tower as well as several of the cities’ neighborhoods such as Montmarte and Goutte D’Or.  Many visited Amsterdam, Barcelona, London, and Rome on their free day.  The course will be offered every year during spring break. For more information,visit our website, YouTube page, or contact Dr. Austin at polssdw@ufl.edu.  Below is a photo of them after hearing a lecture by Professor and Scholar/Activist Louis-Georges Tin.

A picture of Dr. Sharon Austin and her students

Dr. Manoucheka Celeste Wins A Second Book Award!

 

A picture of Dr. Manoucheka
Dr. Manoucheka Celeste, Assistant Professor of African American Studies and Gender, Women’s Studies, and Sexualities Research, recently won the Diamond Anniversary Book Award from the National Communication Association for her book, Race, Gender, and Citizenship in the African Diaspora: Travelling Blackness (Routledge 2017). This Award is given to “the most outstanding scholarly book published during the previous two years.”  For more information, see 2018 NCA Award Winners.  This book also won the 2017 National Communication Association Outstanding Book Award from the African American Communication & Culture Division and the Black Caucus.  Congratulations Dr. Celeste!

AFA Faculty Win Grants!

Intersections grants poster

Several of the African American Studies core faculty members, affiliate faculty members, and advisory board members are members of research teams that have been awarded Intersections Grants from the Mellon Foundation (organized by the Center for the Humanities and Public Sphere).  See the information below and information about each of the four grants

The African American Studies faculty, affiliates, and advisory board members involved in these grants are:

Tanya Saunders, Manoucheka Celeste, Bryce Henson, Ben Hebblethwaite, Paul Ortiz, Nick Vargas, Chris Busey, Agnes Leslie, Stephanie Birch, Katheryn Russell-Brown, Lauren Pearlman, and Sharon Austin.  Sophia Acord and Barbara Mennel of the Center for the Humanities also assisted with these grants.

Popular wisdom says that strong family relationships provide refuge, comfort, and security. Family protects us, soothes our ills, and calms our fears. Epidemiological studies have drawn a positive correlation between strong family support and physical and mental well-being. Now, a team of researchers at the University of Florida has turned that popular wisdom on its head, at least in their study of a population of African American families living in Tallahassee.

The study led by UF doctoral student Kia Fuller revealed a surprising result: African Americans who have a large family network also have high blood pressure. “A lot of studies show that family support generally improves physical and mental health,” said Fuller. “Our results show that it is more complicated than that. Specifically, if you are called upon to give a lot of family support, it can take a toll on your health.”

UF anthropology professors Connie Mulligan, Lance Gravlee, and Chris McCarty have been studying genetic and sociocultural risk factors for hypertension and related racial disparities in African Americans. High blood pressure presents more often in African Americans than their European American counterparts. Even so, this condition is not well studied.

Mulligan, corresponding author of the study said, “Hypertension shows racial disparities, with higher prevalence in African Americans, as do related cardiovascular diseases. In addition to a better understanding of hypertension and blood pressure variation, we are also interested in the genetic and sociocultural factors that underlie racial disparities in health, and we use hypertension as a model to study racial disparities.”

The researchers conducted extensive interviews with 138 African Americans in Tallahassee, Fla., who were asked to name 30 people with whom they were in regular contact. Individuals with higher blood pressure had more family members in their social network. The team also looked at genetic variations at the ACE gene, which stands for angiotensin I converting enzyme gene. Changes in the ACE gene are a powerful predictor of high blood pressure. Previous studies of the ACE gene that the team conducted showed that a novel measure of vicarious racial discrimination is associated with high blood pressure.

This new study recently published in PLOS One continues the work of examining the effects racial disparity have on the health of African Americans, specifically hypertension.

Mulligan noted the significance of family networks that contain many family members. “Phrased another way, lack of diversity of relationships in your network is associated with higher blood pressure,” Mulligan said. “Since African Americans are known to have more family members in their networks than European Americans, this result might help explain some of the racial disparities we see with hypertension and related cardiovascular diseases.”

If you ever feel that your family is making your blood boil, it just might be true.