Aneesh P. H. Bose

Aneesh Bose, PhD

Nkupi+male+with+fry+%28Aneesh+Bose%29.jpg

Integrative research on animal breeding tactics

I use behavioural, physiological, and molecular approaches to understand the evolution of animal behaviour in reproductive contexts. Animals have evolved a staggering diversity of reproductive strategies, and many of these strategies contain puzzling elements that seem to raise endless questions. For example, why is it that individuals of the same sex and species sometimes express vastly different behaviours in order to achieve reproduction? Why do some animals choose to breed in seemingly harsh and extreme environments? Why do some parents abandon, terminate, or even consume their own offspring? How do individuals balance the tasks of caring for offspring at home with seeking mating opportunities elsewhere? These are only some of the questions that motivate my research, which lies at the intersections between traditional behavioural ecology, physiology, and molecular biology. I conduct experiments in the lab and the field to test ecological and evolutionary theory in order to better understand behaviour from both mechanistic and ultimate perspectives. Many of my recent studies have been large-scale, field-based endeavours to understand how the social and physical environments can affect individuals’ behavioural decisions as they vie, or cooperate, for reproduction.

Some shell breeding cichlid species from Lake Tanganyika (illustrations: Alex Viertler)

I use fish as a model system for a variety of reasons. Fish are incredibly speciose and display all manner of care and reproductive tactics. They are convenient to study in both the lab and the field. They live in some of the most amazing places in the world, and they’re just plain fun to work with!


Parental care - as an optimality problem

Animals display an amazing diversity of parental care strategies – while some animals invest nothing into their young, others are prepared to die for their offspring. What drives such variation within and among species? My research program strives to understand the ecological, physiological, and social factors that explain how much a parent should care for their babies, and critically, when they should not care. This involves careful assessment of costs and benefits in the wild, or under naturalistic conditions.

Female Variabilichromis moorii tending to her offspring in Lake Tanganyika (photo: Aneesh Bose)

Example publications:

-Zimmermann H, Bose APH, Ziegelbecker A, Richter F, Bracun S, Natmessnig H, Katongo C, Banda T, Makasa L, Henshaw JM, Fritzsche K, Sefc KM (2021). Is biparental defence driven by territory protection, offspring protection, or both? Animal Behaviour 176: 43-56. [paper]

Bose APH, Houpt N, Rawlins M, Miller JS, Juanes F, Balshine S (2020). Indirect cue of paternity uncertainty does not affect nest site selection or parental care in a Pacific toadfish. Behavioral Ecology and Sociobiology 74: 1-10. [paper]

- Zimmermann H, Fritzsche K, Henshaw JM, Katongo C, Banda T, Makasa L, Sefc KM, Bose APH (2019). Nest defense in the face of cuckoldry: Evolutionary rather than facultative adaptation to chronic paternity loss. BMC Evolutionary Biology 19: 200. [paper]

Bose APH, Kou HH, Balshine S (2016). Impacts of direct and indirect paternity cues on paternal care in a singing toadfish. Behavioral Ecology 27(5): 1507-1514. [paper]


Parental care - and filial cannibalism

At first glance, cannibalizing one’s own offspring appears to be a surprising and counter-intuitive behaviour. Yet, cannibalism and parental care commonly coexist together in many animal taxa. For example, many fishes are notorious cannibals of their young, and we are always learning more about the multitude of factors that can drive animal parents to kill and eat some of their own babies.

Hatched offspring of the plainfin midshipman fish, Porichthys notatus (approx. 6 weeks old) (photo: Aneesh Bose)

Example publications:

Bose APH (2022) Parent-offspring cannibalism throughout the animal kingdom: A review of adaptive hypotheses. Biological Reviews 97: 1868-1885.[paper]

Bose APH, Lau M, Cogliati KM, Neff B, Balshine S. (2019). Cannibalism of young is related to low paternity and nest takeovers in an intertidal fish. Animal Behaviour 153: 41-48. [paper]

- Jindal S*, Bose APH*, O'Connor CM, Balshine S (2017). A test of male infanticide as a reproductive tactic in a cichlid fish. Royal Society Open Science 4(3): 160891. *Co-first authors [paper]

Bose APH, McClelland GB, Balshine S (2015). Cannibalism, competition, and costly care in the plainfin midshipman fish, Porichthys notatus. Behavioral Ecology 27(2): 628-636. [paper]

Bose APH, Cogliati KM, Howe HS, Balshine S (2014). Factors influencing cannibalism in the plainfin midshipman fish. Animal Behaviour 96: 159-166. [paper]


Male plainfin midshipman fish, Porichthys notatus, with his eggs (approx. 2 weeks old) in an intertidal nest (photo: Aneesh Bose)

Parental care - unorthodox choices

Typically, when animals provide parental care, they seek to nurture their offspring in safe and stable environments. But not always… I am therefore also interested in cases of ‘unorthodox’ parental care. This can include situations when parents counter-intuitively select extreme environments to raise their young. An example of this occurs in the plainfin midshipman fish, Porichthys notatus, where males tend to their eggs in the harsh and ever-fluctuating rocky intertidal zone – hardly a place where you would expect to find fish happily breeding.

Example publications:

- Houpt NSB, Borowiec BG, Bose APH, Brown NAW, Scott GR, Balshine S (2020). Parental males of the plainfin midshipman are physiologically resilient to the challenges of the intertidal zone. Physiology and Biochemical Zoology 93(2): 111-128. [paper]

Bose APH*, Borowiec BG*, Scott GR, Balshine S (2019). Nesting on high: Reproductive and physiological consequences of breeding across an intertidal gradient. Evolutionary Ecology 33(1): 21-36. *Co-first authors † Journal cover image (see right) [paper]


Variabilichromis moorii, a biparental cichlid endemic to Lake Tanganyika in which males experience massive pressure from cuckolders (photo: Aneesh Bose)

Alternative reproductive tactics - cuckoldry, etc.

As the old adage goes, “there’s more than one way to peel an orange” (or use your own preferred vernacular), and nature has found this to be true for animal reproduction as well. In many species, individuals can adopt a number of different tactics in order to achieve reproduction. For example, some males may seek to reproduce by courting females or providing them with nuptial gifts, while other males may choose to avoid this hassle and attempt to reproduce coercively or surreptitiously. How are these alternative tactics maintained together in a population and what are the conditions when selection would favour one tactic over another? Much of my work seeks to understand how alternative tactics evolve and how they influence (or are influenced by) other reproductive traits, such as parental care.

Example publications:

- Bose APH, Henshaw JM, Zimmermann H, Fritzsche K, Sefc KM (2019). Inclusive fitness benefits mitigate costs of cuckoldry to socially paired males. BMC Biology 17(2). [paper]

Bose APH, Zimmermann H, Henshaw JM, Fritzsche K, Sefc KM (2018). Brood-tending males in a biparental fish suffer high paternity losses but rarely cuckold. Molecular Ecology 27(21): 4309-4321. [paper]


Guarder male (left) and sneaker male (right) of the plainfin midshipman fish, Porichthys notatus (photo: Aneesh Bose)

Alternative reproductive tactics - dichotomous males

In some species, selection has taken hold of the idea of alternative reproductive tactics and run with it. Divergent male morphs that express vastly different morphologies and physiologies can coexist together in the same population, with each morph specialized to pursue reproduction using a different set of behaviours. For example, in both the plainfin midshipman fish, Porichthys notatus, and the round goby, Neogobius melanostomus, reproductive males can either take the form of large, aggressive, territorial males that court females and care for offspring (so-called ‘guarder males’), or they can be small, stealthy, non-confrontational males that use cuckoldry to steal fertilizations away from other males (so-called ‘sneaker males’). Although the breeding goals of these males are the same, they approach reproduction from very different angles, and my work examines the suite of adaptations that they exhibit to make them successful at what they do.

Male alternative reproductive tactics of the round goby, Neogobius melanostomus (photo from McCallum et al. 2019)

Example publications:

- Miller JS, Bose APH, Fitzpatrick JL, Balshine S (2019). Sperm maturation is associated with faster swimming sperm in males adopting the alternative but not the conventional reproductive tactic. Journal of Fish Biology 2019:1-12. [paper]

- McCallum ES*, Bose APH*, Lobban N, Marentette J, Pettitt-Wade H, Koops M, Fisk A, Balshine S (2019). Alternative reproductive tactics, an overlooked source of life history variation in the invasive Round Goby. Canadian Journal of Fisheries and Aquatic Sciences 76(9), 1562-1570. *Co-first authors [paper]

Bose APH, McCallum ES, Raymond K, Marentette JR, Balshine S (2018). Growth and otolith morphology vary with alternative reproductive tactics and contaminant exposure in the round goby Neogobius melanostomus. Journal of Fish Biology 93(4): 674-684. [paper]


Reproducing - …in public

Animals that live in groups face unique challenges, including how best to share resources and reproduction among group members. Social hierarchies in animal societies are often accompanied by skew in access to resources and matings, with dominants enjoying the perks of being on top. But is it the dominant individuals who have the power to allocate everything, or can subordinates sometimes impose their will? If a groupmate reproduces, should you be happy that your group as a whole is being productive, or should you be worried that a potential competitor is proliferating? My research on social cichlids examines some of these questions in the wild.

A social group of Neolamprologus multifasciatus (photo from Jordan et al. 2016)

Example publications:

Bose APH, Dabernig-Heinz J, Koch L, Grimm J, Lang S, Hegedűs B, Banda T, Makasa L, Jordan A, Sefc KM (2022). Parentage analysis across age cohorts reveals sex differences in reproductive skew in a group-living cichlid fish, Neolamprologus multifasciatus. Molecular Ecology 31:2418-2434. [paper]

Bose APH, Nührenberg P, Jordan A (2021). Female-female conflict is higher during periods of parental care in a group-living cichlid fish. Animal Behaviour 182, 91-105. [paper]

- Gübel J, Bose APH, Jordan A (2021). Social and spatial conflict drive resident aggression toward outsiders in a group-living fish. Behavioral Ecology 32(5), 826-834. [paper]


Other interests - anthropogenic impacts on animal behaviour

Hamilton harbour, a field site for studying fish in polluted environments (photo: Erin McCallum)

I frequently collaborate on a wide variety of topics (see my list of publications). Recently, I have been working in collaboration with ecotoxicologists to examine the effects of chemical pollution on animal behaviour. Chemical contamination in nature can represent a novel selection regime for wild animals, especially since many chemical compounds have the potential to alter behaviours important for reproduction and survival.

Some of this collaborative work includes:

Bose APH, Brodin T, Cerveny D, McCallum ES (2022). Uptake, depuration, and behavioural effects of oxazepam on activity and foraging in a tropical snail (Melanoides tuberculata). Environmental Advances, 100187. [paper]

- McCallum ES, Dey CJ, Cerveny D, Bose APH, Brodin T (2021). Social status modulates the behavioural and physiological consequences of a chemical pollutant in animal groups. Ecological Applications 31(8), e02454. [paper]

- McCallum ES, Bose APH, Warriner TR, Balshine S (2017). An evaluation of behavioural endpoints: The pharmaceutical pollutant fluoxetine decreases aggression across multiple contexts in round goby (Neogobius melanostomus). Chemosphere 175: 401-410. [paper]


Education and employment

B.Sc. - Marine and Freshwater Biology, University of Guelph, Canada (2008 - 2011).

Ph.D. with Dr. Sigal Balshine - Behavioural Ecology, McMaster University, Canada (2012 - 2017).

Postdoc with Dr. Kristina Sefc - University of Graz, Austria (2017 - 2018).

Postdoc with Dr. Alex Jordan - Max Planck Institute of Animal Behavior, Konstanz, Germany (2018 - 2022).

Postdoc with Dr. Tomas Brodin - Swedish University of Agricultural Sciences, Umeå, Sweden (2022 - present).

aphbose@gmail.com