🐟 Can a fish survive in milk?

No, fish cannot survive in milk. Fish cannot breathe properly in milk due to low dissolved oxygen and the presence of impurities in milk. Therefore, fish may drown in milk within a few minutes. Fish cannot survive if they are exposed to foreign environments such as milk, beer, vodka, or other liquids because their body is not evolved for an environment other than water. Even a freshwater fish cannot survive in salt water and vice versa.

Have you ever wondered, can fish swim and survive in milk, coke, beer, or some other liquids other than water.

Before we jump to milk, let us first understand how fish breathe and survive in the water.

Fish don’t have lungs like humans because the human lungs need to be dry to function properly. If fish have similar respiratory systems like humans, then the water will fill these lungs because fish have breathed underwater and they have to extract oxygen from water, unlike humans, extract oxygen from the air. Therefore the lungs won’t function properly for fish underwater. Fish have gills that help them to breathe underwater. These fish gills help to extract oxygen from water. In the breathing process of fish, water first enters through the mouth and then passes through feathery filaments of gills. These filaments of gills are short threads like protein structures and have a capillary network that provides a large surface area for the exchange of oxygen and carbon dioxide. The oxygen absorbed by filaments of gills gets distributed throughout the body with the help of a fish’s heart pump. After the exchange of oxygen and carbon dioxide is complete, the water containing carbon dioxide moves out of the body through gill flaps.

In this way fish absorbs oxygen and remove carbon dioxide to survive in the water.

Milk is consists of almost 87% water but still, milk is not a suitable environment for fish to survive. Fish can easily swim in milk because the density of milk is 1.2 times higher than the density of water and also it has similar viscosity as water. Now let’s look at the conditions that make milk an unbreathable environment for fish.

The presence of lactose, fat, and protein molecules in milk reduces the amount of available dissolved oxygen. The high concentration of minerals, fat, protein, and other contents might clog the gills that would create suffocation for fish to breathe.

The other possible challenge for fish will be the visibility in the milk. It will make it difficult for fish to find food inside the milk unless it moves. It is also possible that the fish might catch infection because they are not evolved to survive in milk.

We can consider milk as a pollutant in water similar to pollutants present in the air. We know that the presence of pollutants in the air causes suffocation and can lead to many respiratory infections for humans. Similarly, for fish, milk is polluted water which makes it difficult for them to breathe and survive.

Similar to milk, in other liquids such as coke, and beer, it will be difficult for fish to survive as they contain more minerals, carbohydrates, fat, and other content as compared to water. Most of the creatures have evolved and survived according to their environmental conditions, therefore, if any creature is exposed to any foreign environment, it is very unlikely for him to survive. Let’s imagine if humans are shifted to mars which has different atmospheric conditions. Do you think humans can survive? Yes, it will difficult for us to survive and it might take us a long time to adapt to the conditions of mars. In a similar way, fish can drown in other foreign liquids for which fish is not ready.

Do you know?

Saltwater fish cannot survive in freshwater and vice versa

It is because of the tonicity of the liquid. Saltwater is a hypertonic solution in which the concentration of salt is higher in the ocean as compared to the concentration of salt in the fish body. Due to this fish lose a lot of water to their surrounding through the process of osmosis. In order to survive, saltwater fish have to increase the intake of water. While freshwater is a hypotonic solution in which the concentration of salt in the fish body is higher than the freshwater reservoir. Due to this water continuously flows into the fish body through the osmosis process. In this case, fish have to urinate water very frequently. Both saltwater and freshwater fishes have evolved their body according to their surrounding conditions.

Now if we put the freshwater fish into saltwater, fish will die of dehydration because their body is not evolved to intake more water. Similarly saltwater fish will also die in freshwater because their body will get swollen with water as their body doesn’t have a habit of urinating frequently.

Therefore, we know that all creatures including fish are evolved according to their environmental conditions and it will be difficult for them to survive if there any fluctuations in their surrounding environment or they are exposed to any new foreign environment.

Read more interesting questions about fish:

Professor Atom

View posts by Professor Atom
Professor Atom is a science enthusiast and alumni of IIT Bombay. According to him, every question can be solved with curiosity and mind mapping. ( Curiosity = Asking Questions = Learning )

Leave a Reply

Your email address will not be published. Required fields are marked *