Now, doctoral research by evolutionary biologist Kathryn Lord at the University of Massachusetts Amherst suggests the different behaviors are related to the animals’ earliest sensory experiences and the critical period of socialization. Details appear in the current issue of Ethology.
Until now, little was known about sensory development in wolf pups, and assumptions were usually extrapolated from what is known for dogs, Lord explains. This would be reasonable, except scientists already know there are significant differences in early development between wolf and dog pups, chief among them timing of the ability to walk, she adds.
To address this knowledge gap, she studied responses of seven wolf pups and 43 dogs to both familiar and new smells, sounds and visual stimuli, tested them weekly, and found they did develop their senses at the same time. But her study also revealed new information about how the two subspecies of Canis lupus experience their environment during a four-week developmental window called the critical period of socialization, and the new facts may significantly change understanding of wolf and dog development.
When the socialization window is open, wolf and dog pups begin walking and exploring without fear and will retain familiarity throughout their lives with those things they contact. Domestic dogs can be introduced to humans, horses and even cats at this stage and be comfortable with them forever. But as the period progresses, fear increases and after the window closes, new sights, sounds and smells will elicit a fear response.
Through observations, Lord confirmed that both wolf pups and dogs develop the sense of smell at age two weeks, hearing at four weeks and vision by age six weeks on average. However, these two subspecies enter the critical period of socialization at different ages. Dogs begin the period at four weeks, while wolves begin at two weeks. Therefore, how each subspecies experiences the world during that all-important month is extremely different, and likely leads to different developmental paths, she says.
Lord reports for the first time that wolf pups are still blind and deaf when they begin to walk and explore their environment at age two weeks. “No one knew this about wolves, that when they begin exploring they’re blind and deaf and rely primarily on smell at this stage, so this is very exciting,” she notes.
She adds, “When wolf pups first start to hear, they are frightened of the new sounds initially, and when they first start to see they are also initially afraid of new visual stimuli. As each sense engages, wolf pups experience a new round of sensory shocks that dog puppies do not.”
Meanwhile, dog pups only begin to explore and walk after all three senses, smell, hearing and sight, are functioning. Overall, “It’s quite startling how different dogs and wolves are from each other at that early age, given how close they are genetically. A litter of dog puppies at two weeks are just basically little puddles, unable to get up or walk around. But wolf pups are exploring actively, walking strongly with good coordination and starting to be able to climb up little steps and hills.”
These significant, development-related differences in dog and wolf pups’ experiences put them on distinctly different trajectories in relation to the ability to form interspecies social attachments, notably with humans, Lord says. This new information has implications for managing wild and captive wolf populations, she says.
Her experiments analyzed the behavior of three groups of young animals: 11 wolves from three litters and 43 dogs total. Of the dogs, 33 border collies and German shepherds were raised by their mothers and a control group of 10 German shepherd pups were hand-raised, meaning a human was introduced soon after birth.
At the gene level, she adds, “the difference may not be in the gene itself, but in when the gene is turned on. The data help to explain why, if you want to socialize a dog with a human or a horse, all you need is 90 minutes to introduce them between the ages of four and eight weeks. After that, a dog will not be afraid of humans or whatever else you introduced. Of course, to build a real relationship takes more time. But with a wolf pup, achieving even close to the same fear reduction requires 24-hour contact starting before age three weeks, and even then you won’t get the same attachment or lack of fear.”Kathryn Lord
Kathryn Lord | Newswise
New approach for environmental test on livestock drugs
27.07.2016 | Universität Zürich
Managing an endangered river across the US-Mexico border
18.07.2016 | International Institute for Applied Systems Analysis (IIASA)
Der Datenverkehr wächst weltweit. Glasfaserkabel transportieren die Informationen mit Lichtgeschwindigkeit über weite Entfernungen. An ihrem Ziel müssen die optischen Signale jedoch in elektrische Signale gewandelt werden, um im Computer verarbeitet zu werden. Forscher am KIT haben einen neuartigen Photodetektor entwickelt, dessen geringer Platzbedarf neue Maßstäbe setzt: Das Bauteil weist eine Grundfläche von weniger als einem Millionstel Quadratmillimeter auf, ohne die Datenübertragungsrate zu beeinträchtigen, wie sie im Fachmagazin Optica nun berichten. (DOI: 10.1364/OPTICA.3.000741)
Die neuentwickelten Photodetektoren, die weltweit kleinsten Photodetektoren für die optische Datenübertragung, eröffnen die Möglichkeit, durch integrierte...
Transparent electronics devices are present in today’s thin film displays, solar cells, and touchscreens. The future will bring flexible versions of such devices. Their production requires printable materials that are transparent and remain highly conductive even when deformed. Researchers at INM – Leibniz Institute for New Materials have combined a new self-assembling nano ink with an imprint process to create flexible conductive grids with a resolution below one micrometer.
To print the grids, an ink of gold nanowires is applied to a substrate. A structured stamp is pressed on the substrate and forces the ink into a pattern. “The...
Mikroben und Viren haben weitreichenden Einfluss auf die Gesundheit von Mensch und Tier. Die neu gegründete "Austrian Microbiome Initiative" (AMICI) fördert die nationale Mikrobiomforschung und vernetzt MedizinerInnen und ForscherInnen verschiedenster Fachrichtungen zur Nutzung von Synergien.
Bakterien, Archaeen, Pilze, Viren – Milliarden von Mikroorganismen leben in Symbiose in und auf Menschen und Tieren. Diese mikroskopisch kleinen Lebewesen...
A new Fraunhofer MEVIS method conveys medical interrelationships quickly and intuitively with innovative visualization technology
On the monitor, a brain spins slowly and can be examined from every angle. Suddenly, some sections start glowing, first on the side and then the entire back of...
Wissenschaftler aus Dresden und Dublin haben einen vielversprechenden technologischen Ansatz gefunden, der Notebooks und anderen mobilen Computern in Zukunft deutlich schnellere Internet-Funkzugänge ermöglichen könnte als bisher. Die Teams am Helmholtz-Zentrum Dresden-Rossendorf (HZDR) und am irischen Trinity College Dublin brachten hauchdünne Schichten aus einer speziellen Verbindung von Mangan und Gallium dazu, sehr effizient Strahlung im sogenannten Terahertz-Frequenzbereich auszusenden. Als Sender in WLAN-Funknetzen eingesetzt, könnten die höheren Frequenzen die Datenraten zukünftiger Kommunikations-Netzwerke spürbar erhöhen.
„Wir halten diesen Ansatz für technologisch sehr interessant“, betont Dr. Michael Gensch, Leiter einer Arbeitsgruppe am HZDR, die sich mit den...
27.07.2016 | Veranstaltungen
26.07.2016 | Veranstaltungen
20.07.2016 | Veranstaltungen