Navigation Links
Personality interactions between animals may dictate outcomes in the wild

PITTSBURGHExamining the varying personality types of multiple animal species at oncein addition to common single-species studiescould help biologists better predict ecological outcomes, according to a recent University of Pittsburgh study.

By observing the interplay in a common predator-prey system (the jumping spider and the house cricket), a team of Pitt biologists found that it was the interactions between the personality types of two species that best predicted survival outcomesand not the personality types of either species alone. Their findings were highlighted in the September print issue of Behavioral Ecology.

"If we're interested in really understanding how individual personalities influence ecology, then we also have to acknowledge and accept that the personalities of many species or groups are also important," said Jonathan Pruitt, assistant professor of behavioral ecology in the Department of Biological Sciences within the Kenneth P. Dietrich School of Arts and Sciences.

The team began by tracking both species' activity levels to determine "personality" or behavior types. They started with the predator, collecting a population of spiders from Pitt's Pymatuning Laboratory of Ecology. The researchers charted individual spiders' activity within a five-minute span, seeing how far they could climb to the top of a vile. Their activity levels were measured, and the tests were repeated over four weeks to ensure that individuals' behavior was repeatable. The team found that some individuals were consistently highly active, whereas other individuals of the same species were more sedentary.

The crickets, which were collected commercially, had a bit of a different test, given their prey status. With room to move in an open field, the Pitt biologists monitored the crickets' reaction times to a new place and their distance covered within five minutes. To ensure repeatability, this test was repeated over 10 days, once every other day. Like the spiders, the individual crickets exhibited different activity levels, where some individuals were highly active and others were more sedentary. The researchers then ranked the crickets' activity levels, grouping them in teams of six based on speed.

For a staged predator-prey cage match, the team placed six crickets "in the ring"a container with enough natural airflowagainst just one solitary spider. The ring was left alone for one week, and cricket mortality rate was measured daily. To accurately determine the crickets' precise cause of death, the team measured cricket mortality rate both in the presence and absence of spiders.

Using their collected data, the Pitt researchers modeled the behaviors of both species, hypothesizing potential outcomes. In addition to their behavioral data, they also took into account the spiders' and crickets' body mass, body conditions, and their individual responses to threats.

Their results closely matched the predictions of the locomotor crossover hypothesisa theory positing that active predators tend to consume inactive prey, whereas inactive predators tend to consume active prey. Pruitt said this finding is actually surprising, given the possibility that the predators and/or prey could have changed their behavioral responses based on their foes' activity levels.

"This implies that the personality types of these spiders and crickets are fairly rigid," said Pruitt. "If either species had been more flexible, they might have sensed the personality types present in their foe and shifted their strategy more strategically."

Their results show that the performance of the spiders depended neither on the average activity level of the spider nor the average group activity of the crickets. Instead, it was the interaction between the activity levels of both groups that predicted survival for the crickets and foraging success for the spiders.

"Our study is one of about four recent studies demonstrating the importance of studying the personalities of multiple species concurrently," said Pruitt. "If we had restricted our focus to only a single species, say the spider, we wouldn't have detected an effect of the spiders' personality at all. This is because, on average, both active and inactive spiders caught a similar number of prey. Only when we consider the personalities of the prey do we see that the performance of active versus inactive spiders depends on the activity levels of their prey."

Pruitt said that, taken together, the Pitt data emphasizes that there is valueor perhaps even a needin broadening the focus of future personality studies beyond just single-species examinations.

"Studies about multiple, interacting species hold promise toward increasing our understanding of the ecological causes and consequences of behavioral variation, which we observe in virtually every animal population," Pruitt said.


Contact: B. Rose Huber
University of Pittsburgh

Related biology news :

1. Friendly to a fault, yet tense: Personality traits traced in brain
2. Personality genes may help account for longevity
3. In elk hunting, success depends on the animals personality
4. Borderline personality disorder: The "perfect storm" of emotion dysregulation
5. New insights into the borderline personality brain
6. Chimpanzees have 5 universal personality dimensions
7. Personality may predict if you like spicy foods
8. Personality may affect a new mothers decision to breastfeed
9. Drug interactions wont exclude HCV transplant or HIV co-infected patients from treatment
10. How bacteria change movement direction in response to oxygen: Molecular interactions unravelled
11. Researchers describe new molecular interactions behind the inhibition of TGF beta-signaling
Post Your Comments:
(Date:4/19/2016)... 2016 The new GEZE SecuLogic ... web-based "all-in-one" system solution for all door components. It ... the door interface with integration authorization management system, and ... The minimal dimensions of the access control and the ... installations offer considerable freedom of design with regard to ...
(Date:4/13/2016)... , April 13, 2016  IMPOWER physicians supporting Medicaid ... setting a new clinical standard in telehealth thanks to ... leveraging the higi platform, IMPOWER patients can routinely track ... and body mass index, and, when they opt in, ... convenient visit to a local retail location at no ...
(Date:3/23/2016)... , March 23, 2016 ... erhöhter Sicherheit Gesichts- und Stimmerkennung mit Passwörtern ... (NASDAQ: MESG ), ein führender ... das Unternehmen mit SpeechPro zusammenarbeitet, um erstmals ... Finanzdienstleistungsbranche, wird die Möglichkeit angeboten, im Rahmen ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... June 23, 2016   Boston Biomedical , ... compounds designed to target cancer stemness pathways, announced ... granted Orphan Drug Designation from the U.S. Food ... gastric cancer, including gastroesophageal junction (GEJ) cancer. Napabucasin ... to inhibit cancer stemness pathways by targeting STAT3, ...
(Date:6/23/2016)... SILVER SPRING, Md. , June 23, 2016 ... evidence collected from the crime scene to track the criminal ... sick, and the U.S. Food and Drug Administration (FDA) uses ... Sound far-fetched? It,s not. ... whole genome sequencing to support investigations of foodborne illnesses. Put ...
(Date:6/23/2016)... ... 2016 , ... Charm Sciences, Inc. is pleased to announce ... Research Institute approval 061601. , “This is another AOAC-RI approval of the Peel ... President of Regulatory and Industrial Affairs. “The Peel Plate methods perform comparably to ...
(Date:6/23/2016)... June, 23, 2016  The Biodesign Challenge (BDC), a ... ways to harness living systems and biotechnology, announced its ... in New York City . ... students, showcased projects at MoMA,s Celeste Bartos Theater during ... , MoMA,s senior curator of architecture and design, and ...
Breaking Biology Technology: