Humans reproduce like rabbits

Why rabbits are drawn to the cities : "It's easier to visit the neighboring building"

Ms. Ziege, how did you come to the conclusion that wild rabbits behave in a similar way to humans?
Rabbits are mammals and have many similarities with us humans that one would not even suspect. Rabbits, for example, are very social animals, they often live in groups, males and females in one burrow. There are clear hierarchical structures that they maintain through intensive communication - almost through communication networks as we humans know them.

Social media in the rabbit hole?
So to speak. In rabbits, communication takes place primarily through scents that are in the faeces and urine. On the one hand, these are hormones from the body, on the other hand, the fragrances come directly from the gland, which is located in the anus, and are added to the feces.

Whether it is reproductive time, whether it is a male or a female, what rank it holds - all of this information is contained in the feces and urine. Rabbits always come to the same places - the so-called latrines. Here they put their feces and urine together and exchange information about them. They don't do that anywhere, they are strategically placed places where the rabbits meet like at an advertising pillar to exchange the latest information.

There are places for communication within your own group, these are very close to the building. Latrines that are further away from the building, on the other hand, serve to separate them from other groups.

People also communicate through sayings on toilet walls.
There are certainly parallels. Latrines are places where everyone has to go - and then notice everything that is new. These are meeting points.

They also found that rabbits behave similarly to humans when it comes to rural exodus.
Living beings are always drawn to where they can find resources, for example food and shelter. I have been studying rabbit populations in downtown Frankfurt am Main since 2011. All of my results indicate that they prefer the busy city because they can find everything they need locally.

They live in full swing, so to speak. It was only the genetic study that confirmed to us that the rabbits that settled in the city immigrated from rural areas - and have been there for many generations. There is currently still an exchange of genes, but mainly from the countryside into the city and not the other way around.

So a new trend?
According to records from the city of Frankfurt, rabbits have been around there since 1930. In a source from 1827 there is even evidence that the animals have been resident in the city since the 19th century. Since rabbits reproduce relatively quickly, the gene flow can be viewed very well. And we have found that the genetic diversity is greater in the city than in the country.

That sounds quite unexpected at first.
Yes, that surprised us. Apparently this is due to the fact that the different groups of rabbits live relatively close together in the city. This makes it easier to visit the neighboring building. The original population was made up of rabbits coming from different directions from the land. This population then met in Frankfurt and could eagerly mix. It looks different in the country.

Here, different groups of rabbits sometimes live so far apart that they hardly mix or not at all.

Again similar to humans.
Indeed, the comparison suggests itself. Different cultures meet in larger cities and sometimes have children together. In particular in the rural regions of the countries of origin, such a mixture does not usually occur to this extent - just think of the increased cases of inbreeding in earlier times in the countryside.

Is there an increase in rabbits in the cities?
There has been a general increase in wildlife in cities, and this has been a trend for several years. In Frankfurt, however, I have observed a decline in wild rabbits in recent years.

What happened?
One answer could be that the once so paradisiacal state no longer exists. I noticed, for example, that the once dense vegetation in the parks has been severely cut back by the Green Spaces Department. There is also a natural process: where many animals live together in close proximity, pathogens, for example, can spread better.

Why were the animals drawn to the city in the first place? It ought to be much better to live in the wild.
No, it's just the other way around. In Frankfurt the rabbits have settled in the inner green strip and in larger park areas. They feel comfortable in the dense hedges and the boundaries of the green spaces. In the surrounding area, on the other hand, agriculture has been intensified in recent decades.

But rabbits need varied structures in which to find cover. It is bad to build a building in open meadows, the enemy pressure is greater there than in the city. Many selection factors that exist in the country are less pronounced in the city.

It's also two or three degrees warmer there. The rabbit burrows are usually a little smaller because roads delimit them. The animals have adapted. But we also found buildings that went under streets.

So how do you study the behavior of wild rabbits in a city?
Behavioral biology has a lot to do with observation. You have to make sure that the rabbits don't feel they are being watched. That was relatively easy in the city because the animals there are used to the presence of people. It was more difficult in the country, where we had to work hidden with binoculars.

In Berlin, foxes roam the city center at night. What do your results say about this?
The extent to which a species adapts to life in the city always depends on the species and the structure of the city. However, general conclusions can be drawn from our results and transferred to cities or mammals of similar size. Ultimately, our cities will play an important role in terms of biodiversity in the future.

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