-Have larger spawns in a single reproductive period

-Death is usually shortly after spawning

-Population has a tendency to crash rapidly or surge rapidly

Has a shorter lifespan as spawning costs a large amount of energy

-Has a smaller size spawn due to lower fertility per reproductive episode

-Allows the parent to care for young increasing infant survival rate

Typically also has a longer lifespan and spawning is less energy taxing on the organism

Advantages:

• Ensures biparental care, increasing offspring survival

• Pair bonding & long-term partnerships enhances genetic diversity

• Reduces risk of STDs

Disadvantages:

• No. of offspring produced is limited

• Reproductive success is reduced if a partner dies/is infertile

• Can lead to intense competition & aggression over mates

Polyandry: One female mates with multiple males

Advantages:

• Improves genetic diversity & increases offspring survival

• Flexibility in mating choices

• Advantageous when females are dominant, reducing male competition

Disadvantages:

• Unequal reproductive success due to risk of males committing infanticide

• Higher energy costs for females

• Increased male competition

Polygyny: One male mates with multiple females

Advantages:

• Allows males to sire many offspring

• Flexibility in mating choices

• Advantageous when males are dominant, reducing female competition

Disadvantages:

• Unequal reproductive success, males may resort to deceptive mimicry or infanticide

• Increases competition & aggression among males

• Males may require more resources to support multiple mates

Most fish species are gonochoristic except wrasses, clownfish etc.

Advantages:

• Higher survival and higher fecundity

• Reaching sexual maturity early

• Separate sees increase genetic diversity

Disadvantages:

• 2 individuals of different sexes have to find each other to reproduce

• Competition for mates

• Mate Availability

• Sexual dimorphism --> showy or distinctive features that attract mates can also attract predators

Advantages:

• Maximizes genetic diversity

• Reduced risk of inbreeding, increasing reproductive success

• Lessens need for territorial defense or long-term pair bonds

Disadvantages:

• Higher risk of STDs

• Reduced parental care & investment, lower offspring survival rates

• Increased survival rates due to high protection & care for developing offspring

• Reduced predation risks

• Enhanced offspring development due to constant monitoring & care

Disadvantages:

• High energy & time investment for parents, sometimes at the cost of their life

• Limited no. of offspring parents can care for

• Parents face increased predation risk

• Increased offspring survival due to protection from predators & environmental hazards

• Allows for territory defense, ensuring resource availability for offspring

Disadvantages:

• Energy & vigilance from parents

• Increased risk of parental injury or death

• Limited parental ability to forage or mate during guarding period

• Safe & controlled environment for offspring development

• Concealed eggs/young = reduced predation risks

Disadvantages:

• Building/maintaining nest is energy & resource intensive

• Nest at risk of predation or environmental destruction

• Parents may be limited in mobility/ability to respond to changing conditions

Some examples of unique hermaphroditic vertebrates include snook, clown fish, wrasse, angelfish, grouper, goby and parrotfish. Some of them change from male to female after maturation, while some were born female and switch to male.

Advantages

• Expanding the pool of potential mates, it may be even possible for them to even fertilize its own eggs

• Increased reproductive success

• Population survival, higher chance of preventing extinction as compared to gonochoristic

  
  

Disadvantages

• Reduced genetic diversity if they were to self-fertilize

• Self-fertlization and maintaining both male and female reproductive organs can be energetically demanding.

  
  

• Genetic diversity and variation,

• enhancing the ability for the offspring to adapt well and even increase reproductive success.

Ovoviviparity (Internal fertilization)

• Eggs are protected within the mother's body, reducing predation risk.

• Mother's body provides a stable environment for the embryo development, ensuring optimal conditions.

• Fertilized eggs are nourished by the egg yolk and a specialized uterine milk produced by the mother.

Delayed Maturity:

• As bowmouth guitar fish takes several years to reach maturity (6-7 years), delayed age of sexual maturity, allows individuals to reach a larger size before reproduction, increasing their chances of survival and reproductive success.