Truffles are not uncommon in the northern hemisphere, but it is really impossible to do it overnight.

In biology, truffles belong to ascomycetes, more specifically, truffles are ectomycorrhizal fungi-they are born with roots.

The mycelium of truffle forms mycorrhizal relationship with the roots of several tree species, including beech, birch, hazelnut, oak, pine and poplar.

Truffles provide valuable trace elements (iron, copper, zinc, etc. ) and a large number of nutrients (potassium, phosphorus, nitrogen, sulfur, etc. ) is used to exchange carbohydrates for plants (hyphae pierce the epidermis to exchange nutrients, but do not pierce the cell wall). Without plant hosts, they can't survive in the soil and can't complement each other.

However, it takes about 7 to 10 years for truffles to form a mycorrhizal network in the forest and stably produce a large number of fruiting bodies.

Different from the familiar mushrooms, the fruiting body of truffles is underground, which is difficult to find and needs to be excavated. In fact, it's not just truffles, it's very common for mushrooms to move their fruiting bodies underground in evolution, and they have appeared independently for countless times throughout the northern hemisphere.

Moving the fruiting body from the surface to the underground is an evolution.

Phylogenetic evidence shows that most underground fruiting bodies evolved from aboveground mushrooms. As time goes on, the stalks and caps of mushrooms decrease, and the caps begin to wrap the reproductive tissues.

Pigs are the most famous. They are naturally looking for truffles, especially sows, and their intention to eat truffles is very strong. This is thought to be because a compound in truffles is similar to androstenol, which is a sex pheromone in the saliva of boars, and sows are strongly attracted.

Therefore, traditionally in Europe, pigs are used to extract truffles. Since the late 1990s, some countries and regions have banned the use of pigs to collect truffles, not because pigs will bite off their fingers, but because they are rude-the destruction of truffle mycelium by pigs during excavation will lead to a decline in productivity.

Instead, today's truffle hunters use dogs instead of pigs. Truffle dogs have no specific breed, but it is better to be puppies so that their claws will not destroy truffles. In addition, dogs do not have a strong desire to eat truffles. Studies have shown that after training, dogs will actively recognize the compound dimethyl sulfide, so they can find the fruiting body.

A basket of truffles is worth a whole month's income, and the puppy is great. Now people's truffle dogs in rural France and Italy are hiding at home like their little ancestors. It is no exaggeration to say that stealing dogs lies in waiting outside every night.