Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists Find Elephant Memories May Hold Key to Survival

13.08.2008
A recent study by the Wildlife Conservation Society and the Zoological Society of London (ZSL) suggests that old female elephants—and perhaps their memories of distant, life-sustaining sources of food and water—may be the key to survival during the worst of times.

In particular, experienced elephant matriarchs seem to give their family groups an edge in the struggle for survival in periods of famine and drought, according to a recently published paper in The Royal Society’s Biology Letters.

“Understanding how elephants and other animal populations react to droughts will be a central component of wildlife management and conservation,” said Wildlife Conservation Society researcher Dr. Charles Foley, lead author of the study. “Our findings seem to support the hypothesis that older females with knowledge of distant resources become crucial to the survival of herds during periods of extreme climatic events.”

Dr Nathalie Pettorelli, ZSL researcher and co-author, added, “Climate change is expected to lead to a higher occurrence of severe drought in Africa and our study suggests that such extreme climatic events may act as a selection force on animal populations. As animals battle to cope certain individuals, such as these grand dames of the elephant kingdom, might become increasingly important.”

Specifically, the study examines patterns of calf mortality during the drought of 1993 in Tanzania’s Tarangire National Park, the most severe drought in that region in the past 35 years. During a nine-month period of that year, sixteen out of 81 elephant calves in the three groups studied died, a mortality rate of 20 percent. The normal mortality rate of calves during non-drought years is a mere two percent.

When compared with other data, researchers noted correlations in calf survivorship with the movements of the groups and, in particular, the ages of the female members within those groups. First, of the three elephant groups observed during the event, the two groups that left the park suffered lower mortality rates than the group that remained in the northern portion of the protected area. The researchers speculated that these elephants succeeded in finding sufficient food and water outside the protected area to keep themselves and their young alive. The group that stayed suffered 63 percent of the mortality for the year.

Second, an examination of the ages of the individual elephants in the three herds was even more suggestive. The data indicated that the age of the mother elephants was an important predictor for calf survival. The two groups that left the park, presumably in search of food and water, had matriarchs that were ages 45 and 38 years of age respectively, whereas the group that remained had a matriarch that was only 33 years of age, the result of heavy poaching during the 1970’s and 1980’s that targeted older females with large tusks.

Third, the researchers pointed out that the groups that left the park may have benefited from the specific experiences of their oldest matriarchs, which perhaps were able to draw upon memories of an earlier drought and how they survived it. The case is strengthened by the known life history of the oldest matriarchs in these groups, some of which were five years or older during the drought of 1958-61. The group that remained in Tarangire in 1993 had no individuals old enough to remember the event.

“It’s enticing to think that these old females and their memories of previous periods of trauma and survival would have meant all the difference,” added Foley. “The data seem to support the speculation that the matriarchs with the necessary experience of such events were able to lead their groups to drought refugia.”

During the 1970s and ‘80s, many of Eastern Africa’s largest elephants fell victim to waves of poachers who were eager to exploit the profitability of the black market for ivory.

“Hopefully, this study underlines the importance of how crucial older matriarchs are to the health of elephant populations,” added Foley. “Protecting the leaders of elephant herds will be even more important in what may be an increase in droughts due to climate change.”

Stephen Sautner | Newswise Science News
Further information:
http://www.wcs.org

More articles from Studies and Analyses:

nachricht Self-organising system enables motile cells to form complex search pattern
07.05.2019 | Westfälische Wilhelms-Universität Münster

nachricht Mouse studies show minimally invasive route can accurately administer drugs to brain
02.05.2019 | Johns Hopkins Medicine

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Successfully Tested in Praxis: Bidirectional Sensor Technology Optimizes Laser Material Deposition

The quality of additively manufactured components depends not only on the manufacturing process, but also on the inline process control. The process control ensures a reliable coating process because it detects deviations from the target geometry immediately. At LASER World of PHOTONICS 2019, the Fraunhofer Institute for Laser Technology ILT will be demonstrating how well bi-directional sensor technology can already be used for Laser Material Deposition (LMD) in combination with commercial optics at booth A2.431.

Fraunhofer ILT has been developing optical sensor technology specifically for production measurement technology for around 10 years. In particular, its »bd-1«...

Im Focus: The hidden structure of the periodic system

The well-known representation of chemical elements is just one example of how objects can be arranged and classified

The periodic table of elements that most chemistry books depict is only one special case. This tabular overview of the chemical elements, which goes back to...

Im Focus: MPSD team discovers light-induced ferroelectricity in strontium titanate

Light can be used not only to measure materials’ properties, but also to change them. Especially interesting are those cases in which the function of a material can be modified, such as its ability to conduct electricity or to store information in its magnetic state. A team led by Andrea Cavalleri from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg used terahertz frequency light pulses to transform a non-ferroelectric material into a ferroelectric one.

Ferroelectricity is a state in which the constituent lattice “looks” in one specific direction, forming a macroscopic electrical polarisation. The ability to...

Im Focus: Determining the Earth’s gravity field more accurately than ever before

Researchers at TU Graz calculate the most accurate gravity field determination of the Earth using 1.16 billion satellite measurements. This yields valuable knowledge for climate research.

The Earth’s gravity fluctuates from place to place. Geodesists use this phenomenon to observe geodynamic and climatological processes. Using...

Im Focus: Tube anemone has the largest animal mitochondrial genome ever sequenced

Discovery by Brazilian and US researchers could change the classification of two species, which appear more akin to jellyfish than was thought.

The tube anemone Isarachnanthus nocturnus is only 15 cm long but has the largest mitochondrial genome of any animal sequenced to date, with 80,923 base pairs....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

SEMANTiCS 2019 brings together industry leaders and data scientists in Karlsruhe

29.04.2019 | Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

First dust conference in the Central Asian part of the earth’s dust belt

15.04.2019 | Event News

 
Latest News

Innovative powder revolutionises 3D metal printing

19.06.2019 | Materials Sciences

'Alexa, monitor my heart': Researchers develop first contactless cardiac arrest AI system for smart speakers

19.06.2019 | Information Technology

Clean lungs thanks to laser process exhaustion

19.06.2019 | Machine Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>