Media releases

• Friends to the end? Social cues cause fish to delay survival tactic

  Thursday, November 01, 2018 | By Brock University

  MEDIA RELEASE: 1 November 2018 – R00193

  Getting into trouble after succumbing to peer pressure isn’t just a human experience.

  New research co-led by Brock University shows that a particular species of tropical, air-breathing fish that can survive for weeks on land will delay escaping from hot water if it thinks one of its peers is nearby.

  Brock biologist Glenn Tattersall and Acadia University biologist Suzanne Currie studied the mangrove rivulus, a fish living in swamps from the southern U.S. to Brazil.

  In previous research, Tattersall and fellow researchers found that the mangrove rivulus, which look like miniature sardines, jump out of water at around 35°C as a way of cooling down quickly or else risk dying. They can survive for up to 20 days out of water.

  The research, published in 2015, suggested that fish that can take advantage of evaporative cooling may have an evolutionary advantage over fully aquatic fish in coming years as coastal waters warm because of climate change.

  But the mangrove rivulus is also known to be highly social. Tattersall and Currie wanted to know if, and to what impact, social behaviour would affect the fish’s survival strategy.

  The researchers gathered a group of fish in Belize and placed each fish in its own water chamber. Half of the chambers had a mirror to make it appear there was a second fish in the water.

  The researchers heated the water at a steady, rapid rate while recording the fish’s movements. The experiment ended when the fish jumped out of the water.

  Fish that saw themselves in a mirror stayed in the chamber until the water reached 41.8°C compared to a water temperature of 40.5°C for fish in the chamber with no mirror.

  The fish with the mirror also showed less pre-escape behaviours such as swimming to the surface or poking its head out of the water.

  Tattersall says the results show that the mangrove rivulus prioritize social interaction over escape until they are “perilously close” to the maximum temperature at which they can survive.

  He says the delay could be because the fish is waiting for other members of the group to emerge first.

  “Understanding how the social and physical environment interact is important when determining an animal’s susceptibility to climate warming,” says Tattersall. “This discovery demonstrates that behavioural decisions may push animals to their thermal limits and compromise survival at high temperatures.”

  The research team’s findings are in their paper, “Social cues can push amphibious fish to their thermal limits,” published Oct. 31 in the journal Biology Letters.

  The Natural Sciences and Engineering Research Council of Canada (NSERC) funded the team’s research.

  For more information or for assistance arranging interviews:

  * Dan Dakin, Manager Communications and Media Relations, Brock University ddakin@brocku.ca, 905-688-5550 x5353 or 905-347-1970

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  Categories: Media releases

• Brock research says walking is an ideal activity for people with osteoporosis

  Wednesday, October 31, 2018 | By Brock University

  MEDIA RELEASE: 31 October 2018 – R00192

  As Osteoporosis Month kicks off on Thursday, Brock University Kinesiology Professor Philip Wilson has some simple but effective advice for those living with the disease: lace up your shoes and get walking.

  Osteoporosis is a disease affecting one in four women and one in eight men over the age of 50 that causes chronic loss of bone density and deterioration of bone tissue. New Brock research has found that walking is the most preferred physical activity of people who have the disease, in addition to being an ideal form of exercise for them.

  “Research has clearly demonstrated that for people who live with osteoporosis, physical activity confers a host of benefits,” says Wilson.

  Among the benefits are better fitness, weight loss, improved strength and a better quality of life.

  “There’s also a substantial level of bone integrity when combined with the right medications,” he says.

  While this fact is widely known, health-care initiatives have tended to offer people living with osteoporosis exercise programs such as aerobics classes, weight training or sports events, activities that rate very low on people’s preferences.

  “The literature in the motivational area is very clear: people tend to do what they prefer to do, and they tend to shy away from things that they don’t like to do,” he says.

  Wilson, along with Professor of Kinesiology Diane Mack and graduate student Caitlin Kelley, examined data extracted from the 2009 Canadian Community Health Survey, a joint initiative by the Canadian Institute for Health Information, Statistics Canada and Health Canada.

  The survey collected raw data on a variety of health-related factors that researchers can use to investigate how to improve health. The survey listed 21 common activities in categories of active transportation such as bicycling, sports and structured exercises, such as aerobic classes.

  Participants were asked to indicate if they had done that activity during the past three months. They could also list other activities that were not identified in the survey.

  “More than 60 per cent of both men and women said walking was their No. 1 activity,” says Wilson. “Gardening and yardwork were done by about 35 to 45 per cent of respondents, depending on whether they were male or female, and 22 to 23 per cent identified home-based exercises. Then the numbers drop off really dramatically.”

  Wilson says this research yields valuable clues for health-care professionals designing exercise programs for people living with osteoporosis.

  “The biggest recommendation is, if you want to get, or keep, these people active, you might want to start developing walking programs because it seems that is what this cohort is telling us they want to do.”

  Walking has many benefits: it’s low-budget; can be done at any time; doesn’t require specialized equipment or space; and is typically a low-impact form of exercise. Similar studies have shown that people living with cancer and cardiac diseases also identify walking as their top choice for exercise.

  Wilson says the next step in the research is to find out more about the walking habits of people living with osteoporosis such as where and when they walk, and if they do so alone or with someone else.

  The research team’s findings are in their paper, “Modes of physical activity reported by older adults living with osteoporosis in Canada,” appearing in Health & Fitness Journal of Canada.

  For more information or for assistance arranging interviews:

  * Dan Dakin, Manager Communications and Media Relations, Brock University ddakin@brocku.ca, 905-688-5550 x5353 or 905-347-1970

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  Categories: Media releases