In addition to the primary sexual characteristics - the difference between the ovaries and testes - people mainly use secondary sexual characteristics (or secondary sexual characteristics) to identify the sex of fish. However, secondary sexual characteristics are usually more obvious during the reproductive season, and it is difficult to accurately distinguish them at other times.
In most cases, female fish are larger than male fish, with a swollen abdomen and a slightly protruding genital opening. Male fish often show variations in fins and snouts, such as elongated fins, and elongated and curved snouts and jaws of salmon.
Many fish undergo color variations during the reproductive season, and male fish appear bright colors. Some male fish have pearl stars on their bodies, especially on the snout and pectoral fins. Some fish also have pearl stars on many parts of the head and anal fins.
Male individuals of some fish become aggressive during the reproductive season. When male fish meet or compete for mates, they often "fight".
animal tags：
you may also like
There are many kinds of natural enemies of birds. Here are some of the more common ones:1. Carnivores: Cats, dogs, foxes and bears are all natural enemies of birds. These predators use their speed and strength to hunt down and attack birds.2. Reptiles: Reptiles such as snakes, lizards, crocodiles, e...
Some of the most intelligent turtle species, but it’s impossible to rank them in the top ten. Here are some turtles with higher intelligence: 1. Aldabra tortoise: This tortoise lives in the desert and eats grass as its main food source. They are good at remembering the l...
Mules are usually hybrids resulting from the cross between a donkey and a horse. The main reasons why mules are unable to have offspring are as follows: 1. Genetic factors: Mules have donkey and horse chromosomes that do not exactly match, causing the normal function of t...
Different zoos display different types of animals, usually based on factors such as geographical location, climate conditions and visitor demand. Here are some common zoo animals:1. Large mammals such as lions, tigers, leopards, bears, etc.2. Interesting small mammals such as monkeys, giraffes, kang...
Bullfrogs and frogs are two different species of frogs. They have many differences in appearance, living habits and ecological niches. bullfrog Physical characteristics: Bullfrogs usually have larger bodies, well-developed hind legs, round heads, and oval-shaped...
Canadian law strictly limits the private breeding, sale and trade of big cats, including tigers, lions, leopards, etc. Therefore, ordinary citizens or private individuals are not allowed to breed tigers in Canada. Only institutions or individuals with specific professional qualifications, such as le...
Yes, dogs can trace their ancestry back to wolves. Modern dogs are the result of thousands of years of domestication and artificial selection between humans and wolves. Based on genetic and archaeological research, scientists believe that the earliest ancestor of modern dogs was the gray wolf...
Yes, butterflies belong to the animal kingdom. Butterflies are a species of insects, specifically the order Lepidoptera, which includes all butterflies and moths. The following is a detailed introduction to butterflies:Classification of the Animal KingdomKingdom: AnimaliaPhylum: ArthropodaClass: Ins...
Email: jsset#163.com (change # to @) Please indicate your purpose of visit! Guangdong ICP No. 2022053326 XML| map| Chinese
