LIFE HISTORY VARIATION AND MATING SYSTEM

Life history variation involving burrow-living and symbiosis with other marine invertebrates has given rise to pair-bonding monogamous mating system in several caridean shrimps. This system could further evolve into social mating systems, in which both males and females protect the habitat to overcome predation in a crowded environment. Several caridean shrimps have adapted to live in specialized bioshelters such as living sponges, providing the symbiotic shrimps both protection and food. Specialization of mating associations, as necessitated from this physiological and ecological adaptiveness has also resulted in advanced social formation of community living as well as eusocialization, primarily in aquatic environment (see below).

TYPES OF MATING SYSTEMS

From an evolutionary perspective, the type of mating behavior in a species is a product of sexual selection for increasing the reproductive success. As for the crustaceans, sexual selection, which arises from intraspecific competition for mates, takes the form of sexual phenotypes such as the large claws in gonocho- ristic forms (eg, fiddler crab Uca sp.), whereas in the hermaphroditic taxa, it is evidenced as elaborate courtship and copulatory behaviors. Thus, the assumption of a particular mating system in a population depends mainly on the reproductive potential of a particular male, facilitated by its access to females as well as the female’s choice of the opposite sex. With reference to reproductive or fertilization success, mating systems are classified into social and genetic mating systems (Avise, 2007). Social mating system includes pair-bonding monogamous mating, whereas genetic mating system is more prevalent among polygamous males, which achieves more reproductive success than the social mating system. Nevertheless, different types of mating systems have evolved independently in different taxa in response to environmental conditions to which the animals have adapted to live and reproduce.

The basic mating systems in Crustacea are monogamy and polygamy; Table 4.1 summarizes various subdivisions under the two main categories— monogamy and polygamy.

TABLE 4.1 Mating Systems in Crustaceans

Type of Mating System

Definition

Species

References

1. Monogamy

Each male and female has only one mate

Stenopus

hispidus

Johnson

(1969)

1.a. Social monogamy

Social monogamy refers to the exclusive mating of one male with one female. This mating bonding is usually sustained through one mating season or could extend throughout the adult life of the individuals

Pontonia

margarita

(Caridea)

Baeza and Thiel (2007)

1.b. Persistent pairs

Males seek out, remain with and provide parental care for isolated, synchronously receptive females

Spongicola

levigata

(Stenopodidae)

Hayashi and Ogawa (1987)

1.c. Sequential pairs

After mating with one female, the male leaves the cavity after the female spawns and seeks out for subsequent females in a serial manner

Gonadactylus

bredini

(Stomatopoda)

Shuster and Caldwell

(1989)

1.d.

Eumonogamy

This is true monogamy. The male and the female form a cooperative pair to inhabit and guard a burrow together

Hemilepistus

reaumuri

(Isopoda)

Wickler and Seibt (1981)

2. Polygamy

A mating system in which at least some individuals have multiple mates. Four subtypes are recognized under polygamy

Pandalus sp. (Caridea)

Charnov

(1982)

TABLE 4.1 Mating Systems in Crustaceans—Cont'd

Type of

Mating System Definition Species References

2.a. Polygyny

Particular males may have multiple mates, but each female typically has only one mate

Uca

paradussimieri

(Brachyura)

Murai et al. (2002)

2.b. Polyandry

Particular females have multiple mates but each male has only one mate

Rhyncocinetis typus (Caridea)

Thiel and Hinojosa (2003)

2.c.Polygynandry

Members of both genders typically have two to several mates each. Promiscuity is an extreme form of polygynandry in which each male and female has many mating partners

Uca lactea (Brachyura)

Kim et al. (2004)

3. Eusociality

Only a single reproductive female with eusocial colony organization having strong reproductive skew

Synalpheus

neptunus

neptunus

(Alphidae);

Synalpheus

regalis

(Alphidae)

Didderen et al. (2006) and Duffy and Thiel (2007)

4. Mass mating Semelparous mass mating

Both males and females are characterized by single reproductive cycles over the course of its lifetime

Mancocuma

stellifera

(Cumacea)

Guewuch and Croker (1973)

Iteroparous mass mating

Both males and females are characterized by multiple reproductive cycles over the course of its lifetime

Geocarcinoides

(Brachyura)

Seeger (1996)

5. Aggregational mating by neotenous males

Several neotenous males clinging on to the ventral region of the female, depositing spermatophores at the same time

Emerita asiatica (Anomura)

Subramoniam

(1977a)

 
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