Offspring desertion and infanticide behavior in animal behavior

Topic: Offspring Desertion and Infanticide Behavior

Thesis : Most acts of offspring desertion and infanticide are rooted in some form of survival.

I. Maslow’s Hierarchy of Needs

Michaels, L., (2017). Hierarchy of Dog Needs.

http://www.dogpsychologistoncall.com/hierarchy-of-dog-needs-tm

Maslow’s Hierarchy of needs has been widely accepted into the world of human

psychology. Interestingly enough the world of veterinary medicine have begun to implement

their own version titled ‘Hierarchy of Dog Needs’ to better understand the behaviors and

psychology of dogs. Understanding the motivations of why dogs behave the way they do

contributes to humans being able to better care for the as pets. This model explores the

importance to understand underlying elements for behavior for healthy coexistence for both

animal and human. Dr. Michaels identifies the necessity of understanding the basic needs in

animal nature so we may do better at meeting those needs. While also teaching us that aggressive

behaviors tend to stem from some basic needs being neglected or lacking for our animals.

A. Basic Needs

1. Physiological/Biological needs

a) Food, water, shelter, sex, sleep, homeostasis, excretion of wastes

2. Safety

a) Security of all things : self preservation, resources, health, territory

B. Psychological Needs

1. Love/Belonging

a) Social acceptance, positive contributions to the group

2. Esteem

a) Respect of others, hierarchy of power, dominance

C. Self-Fulfillment Needs

1. Self-Actualization

a) Morality, problem solving, creativity, acceptance of facts, lack of prejudice

II. Types of Infanticide

Palombit, R. A., (2015). Infanticide as Sexual Conflict: Coevolution of Male Strategies and

Female Counterstrategies. Cold Spring Harbor Perspectives in Biology

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4448612/

Palombit explores the adaptive and coevolutionary nature of infanticidal behaviors of

male species in response to sexual conflict. Palombit also explores how the females of the

species have evolved counter strategies in response to their male counterparts behaviors. This

article highlights the fitness benefits received or gained for the male perpetrators committing the

acts of infanticide. While also highlighting the expensive fitness costs being paid by the females

that are having the infanticidal acts committed against their young. This article uses comparative

data to understand why the practice of infanticide has proven to be beneficial for some species

taxa, but not all. Another informative point of analysis in this article details how the females have

adapted strategic responses to combat infanticide.

A. Males

1. Sexual conflict/dominance, fitness

a) Kill existing young to mate and reproduce their own offspring

2. Resource competition

a) Infant is source of nutrition

3. Sexual Frustration/ desperation

a) Sea otters

3. Surplus killing

a) For sport

B. Females (Natures version of abortion)

1. Environmental stressors : pathological response to abnormal stressors

a) Zoo/captivity

I. Zoo Elephants (may not recognize an infant, lack of social introduction to

change, lack of social needs being met for paternity, etc.)

II. Hamsters (solitary and nocturnal creatures)

2. Protecting young

I. Killing of older offspring to give their newest litter a chance to thrive

3. Lack of resources

4. Culling of young for resource competition purposes

I. Weak, deformed, small, sickly young

II. Snowy egrets (third egg sacrifice)

5. Self-preservation

I. Kangaroo/joeys

6. Emotional fulfillment

I. Chimp/ Gorillas steal another moms babies to “play” mom

II. Humans

1. Hormonal deficiency

2. Relational

3. Munchaunsen Syndrome

III. Types of Offspring Desertion (Natures version of adoption)

Pogany, A., Szentirmai, I., Komdeur, J., Szekely, T. (2008). Sexual Conflict and

Consistency of Offspring Desertion in Eurasian Penduline Tit Remiz pendulinus.

Part of Springer Nature, BMC Ecology and Evolution.

This scientific article explores the numerous differences as it pertains to parental

investments between males and females. The biological differences between males and females

are shown to contribute to sexual conflicts and ultimately spills over into the parental provisions

for the young. This article highlights the fitness rewards associated with the abandonment of

offspring typically at the fitness cost of ones mate. This article examines why the absent parent

varies among populations, meaning it could be the male or the female that leaves leaving the

other to rear the young. It also explores the percentage of the young that are abandoned by both

parents and ultimately do not survive.

A. Parental Investment Theory (Robert Trivers)

1. Notes that males in many species do not need to invest as many resources in offspring

as females do and, as a consequence of this sex difference, natural selection should generate a

host of sex-differentiated adaptations and counter adaptations.

B. Operational sex ration

1. The ratio of sexually active males to sexually receptive females at any given time

2. Key behavioral difference in sexes

3. Natural response amplified by variation in the degree to a female and male provide

parental care for their offspring

I. Males

a). Many male animals do not participate in the rearing of their young

i) Bears, lions, sand goby, assassin bug

II. Females

a). Abandon at birth

i) Snakes, Panda bears and Merino sheep (twins)

b). Brood parasites

ii. Brown-headed cowbirds