Manta Ray Genetics & Evolution
By: Brie von Beren
Mating:
- Mating seasons vary in Japan it occurs in summer, but in the Maldives in mid fall
- Warm water
- Cleaning stations
- Males jump from water to impress females
- Hormones are released that attract rays to each other
Mobula Rays belly flop to attract a mate - Shark: Episode 2 Preview - BBC One
Reproduction:
- The manta ray shares many similar reproduction characteristics as many species of sharks
- Manta ray give birth to live pups, but they hatch from eggs
- Although animals that give live birth are called mammals, they are called oviparous meaning: the species gives birth to a live pup that hatches from an egg inside the mother
Sexual union of a male and female this means the male enters the copulatory organ called the claspers in the female cloaca to transfer sperm and start the fertilization process
Incubation:
- Female carries pup for 12-13 months
- Can give birth to up to two pups at once
- Pups feed on yolk for nuetriance
- Once pups are born there independent
Sub-species:
- There are not many sub-species of manta rays there are two kinds of manta ray there is the Manta alfredi and the Manta brostris
- They are very much the same but one is more commonly found in shallow waters off of reefs, and others in deeper water
- Different coloring around the mouth area
Evolution:
- Evolved from bottom-dwelling stingrays
- Many adaptations
- More wing-like pectoral fins
- Barbed spine non-poisonous
- Became filter feeders
Adaptations:
The manta ray has many adaptations that allow it to thrive on a daily basis. One of the major ability the manta ray has is it has the ability of giving birth to a pup without the flow of oxygen from the placenta. The manta ray embryo obtains oxygen by buccal-pumping of uterine fluid, just like fish and how eggs obtain oxygen through the water.
Punnett Square:
The Phenotypes for manta rays are:
Albino (aa) or Black (Aa)
Spotted (AA) or Plain (Aa)
Long tail (Aa) or Short tail (Aa)
Punnett square 1- 1/2 black: 1/2 albino
Punnett square 2- 1/2 spotted: 1/2 plain. 50% of the offspring will have both traits.
Punnett square 3- phenotype: black 3: albino 1. Genotype: AA 1: Aa 2: aa 1
XBXB= black (female)
XBXb= black with recessive albino trait (female)
XbXb= albino (female)
XBY= black (male)
XbY= albino (male)
Punnett square 4- 50% of the female offspring will have the recessive albino trait.