Transcript - Catalyst
Social Behavior What is it? Typically defined as behavioral interactions among individuals within a species. Communication, competition, cooperation, dominance, etc. Can be direct or indirect interactions, and past interactions may have long-term consequences. Female eavesdropping in Black-capped chickadees Mennill et al. 2002 Song sparrows learn more songs from eavesdropping than from direct interaction with tutor % of songs learned Juvenile song sparrows preferentially approach interacting adults Left: Playback of adult song or juvenile song to adults: adults always respond more strongly to adult song. Juveniles are tolerated by adults. So why do juveniles not interact directly with adults? Templeton et al. 2010 Templeton et al. 2012 Good Neighbor/Bad Neighbor in Song Sparrows Akcay et al. 2009 Song sparrows remember the guy who sang from “intruder boundary” and respond more strongly to him even when he sings from the right place later on. Mike suggested that other males in the area may eavesdrop on these interactions and note who in the neighborhood is a “bad neighbor”. Long-tailed manakin “young boy networks” What matters is how many connections you had early in life. The larger the node, the more social connections you have. Note the path of * through life. Adult dancer plumage Juvenile definitive plumage •All alphas were bigshots in early life • i.e. they had a lot of guys “friending” them, while they submitted “friend requests” to the right adults. Conclusions • Indirect interactions (e.g. eavesdropping) may be as important as direct interactions. • Birds may have a longer memory than we think for direct and indirect interactions that occurred in the past. Cooperative hunting Hunting and foraging: several individuals take part in the search of food (probably related—kin selection at play, but can evolve if everyone gets more food on average than they would hunting alone. Benefits: higher success accessing resources, or trapping food Costs: social status may determine the access to the resource even if helped obtaining it. Some don’t get their fair share. http://www.youtube.com/watch?v=_gzc32LGhjI http://www.youtube.com/watch?v=Ai3eVjr0Pzg Social networks in Seattle crows • Communal roosts (including one on Foster Island near the 520 bridges) serve as information centers • Get to know the most successful crows and follow them to prime feeding areas the next day The following examples are NOT social behavior because interactions are between different species. African Honey Guides and Humans Birds and other mammals, including bipedal primates! http://www.youtube.com/watch?v=SN5igku_kGk Mixed species foraging flocks • Mixed species flocks: canopy, understory (hierarchies determine the diversity and abundance of members) • Each species feeds differently so as to avoid competition, and may rustle out food that another species likes. • Interactions may be competitive or mutualistic. Two species of tree creepers found in the Neo-tropics. http://www.youtube.com/watch?v=7Ljm1ZmdySo&feature =related Other associations • Non-human primates and birds: (insects scared by monkeys are taken by birds, others take seeds or fruits dropped while the troop is passing) • Egrets and cattle (Butler 2008): (feeding on food scared up by or other ungulates). • Oxpeckers and cattle. Oxpeckers eat some ticks off the cattle, but mostly suck blood out of the cattle’s ears. • Army ants and Ant birds: army ants (Eciton burchelli), go on raids and birds take anything the ants scared up but missed on their raid Ant bivouac Competitive Interactions • Efficiently divide niche space such that each species has a resource it is most adept at using. • Or: Actively prevent others from using resource, or make it so energetically costly that use of that resource is not worthwhile for others