Spiders picky meals to survive

Scientists from Masaryk University (Czech) have discovered a special phenomenon: many species of insects and predators, including humans, choose to eat certain parts of the prey to balance the amount of nutrients put into the body.

Choosing what to eat is not so important to people when entering the dinner table. However, for some carnivores like spiders or wild cats, they eat only one or two special parts on the prey.

The study published in the Animal Behavior Week, described for the first time how carnivores get a balanced diet. This choice can be driven by the impulse of hunger. For example, with ants eating Zodarion, the main object of the study, hunger prompted them to eat the ant's head, legs or intestines.

Stano Pekar, the lead researcher, said: 'When the spiders choose very different parts of their prey to eat, we hypothesize that they will choose what hunger drives with the most nutritious. determined. They are completely based on need '.

To test, the researchers collected more individual Zodarion spiders. This is a nocturnal, small and very rare spider.

Spiders choose to eat certain parts of ants, according to their nutritional needs, have a higher survival rate than those who eat the entire ant.

The first test was conducted: researchers prepared and analyzed nutritional meals for spiders with menus of different ants.

The menu includes: all ants, abdomen ants, ant heads and other appendages. Their goal is to analyze the choice of spiders when eating different menus and their survival rates during the inspection period.

As a result, the survival rate of spiders depends clearly on the menu it chooses. The spiders eat the entire ants with a worse survival rate than the spiders only select and eat certain parts of the ant.

This is because each part of the ant provides different substances. The ants' legs are high in nitrogen, while the head is high in protein, while the abdomen is high in fat, providing more calories.

Research on choosing to eat certain parts of the body only applies to certain species of spiders, insects and animals. For example, some cat species, such as leopard or lion, are often restricted to their meals with prey such as antelope (with gorillas) or zebras (with lions).

They also select certain parts of their prey and leave all other parts for other animals. For example, when protein is needed, they choose to eat muscle tissue, and if lipids are needed, they only choose to eat fat.

People also have a certain choice. Although we can eat a lot of foods every day, we tend to choose high-calorie foods. This is reflected in the fact that we often prefer to eat fried meat rather than boiled vegetables. The reason is in the substance content.

High-energy foods like chocolate, fried foods, and fried foods often contain the most calories in each unit of mass, while fruits and vegetables have less energy.

Besides, the choice of food also changes according to body condition. This is quite evident in pregnant women. They have a distinctly different choice of foods during different pregnancies, when they reach three, six or eight months. This relates to the need for certain types of maternal nutrition to provide for the development of the fetus.

For those who want to lose weight, the best way is not to try to control the craving for high calorie foods. Instead, limit their exposure to that kind of food, or replace them with similarly flavored but less calorie substitutes.