Our goal is to understand how cognition evolves. How are the building blocks of learning, memory, decision-making and causal inference put together to build a mind? How do these ingredients multiply, duplicate and specialize over ontogenetic and evolutionary timescales? This is our framework of Cog-Evo-Devo.
Our first line of research focuses on the most universal of cognitive traits, the ability to orient in space. All mobile animals, vertebrate or invertebrate, must track the locations of prey, predators, mates and competitors and they do so in similar ways, particularly in their use of odorants. How such convergences evolve across macroevolutionary time is one focus of our research. Spatial cognition also evolves via microevolutionary processes, as individuals adapt to their spatial ecology. Our work documents how a mammal’s ecology predicts its spatial cognitive abilities and hippocampal structure, which vary by species, sex, season and age. Such patterns emerge as predictions from the parallel map theory, an evolutionary model of orientation and hippocampal function (PMT; Jacobs & Schenk, 2003). PMT describes how Tolman’s cognitive map is an integration of parallel spatial representations of space, the bearing and the sketch maps, constructed by complementary hippocampal subfields. This integration creates a flexible and robust cognitive structure for orientation. PMT offers a unitary explanation not only for taxon differences in spatial orientation but also for sex differences, as described in our work on humans (both children and adult) and rodents (both wild and domestic).
Our second line of research investigates how cognitive evolution is shaped by social selection, the selective pressure generated by within-species competition. Cognitive sex differences, for example, are a byproduct of sexual selection, a form of social selection. Social selection also drives species-specific cognitive specializations, such as spatial memory in scatter hoarding birds and mammals. Our current research focuses on the decisions involved in delaying the use of an item to a later time, such as those decisions made by wild fox squirrels in choosing to eat or cache an item and, if caching, how to distribute the caches in space. We study how these decisions are affected by the perception of scarcity and social competition, both in in free-ranging Berkeley campus fox squirrels and free-ranging Berkeley undergraduates.
(updated, March 2014)
Delgado, M.M., Nichols, M., Petrie, D.J. & Jacobs, L.F. (2014) Fox squirrels match food assessment and cache effort to value and scarcity. PlosONE in press.
Jacobs, L.F. & Randolf Menzel (2014) Navigation outside the box: what the lab can learn from the field and what the field can learn from the lab. Movement Ecology 2: 3. DOI 10.1186/10.1186/2051-3933-2-3.
Bettis, T. J., & Jacobs, L. F. (2013). Sex differences in memory for landmark arrays in C57BL/J6 mice. Animal Cognition, 16(6), 873–882
Jacobs, L. F. (2012). From chemotaxis to the cognitive map: the function of olfaction. Proceedings of the National Academy of Sciences, 109, 10693–10700.
Waismeyer, Anna S., & Jacobs, Lucia F. (2012). The emergence of flexible spatial strategies in young children. Developmental Psychology 49, 232-42.
Chai, Xiaoqian J., and Jacobs, Lucia F. (2012). Digit ratio predicts sense of direction in women. PloS One 7, e32816.
Chai, Xiaoqian J., and Jacobs, Lucia F. (2010). Effects of cue types on sex differences in human spatial memory. Behavioral Brain Research 208, 336-342.
Waisman, Anna S., and Jacobs, Lucia F. (2008). Flexibility of cue use in the fox squirrel (Sciurus niger). Animal Cognition 11, 625-636.
Jacobs, L. F. (2006). From movement to transitivity: the role of hippocampal parallel maps in configural learning. Reviews in the Neurosciences, 17(1-2), 99–109.
Jacobs, Lucia F., and Schenk, Françoise. (2003). Unpacking the cognitive map: the parallel map theory of hippocampal function. Psychological Review 110, 285-315.