 Hello everybody, we are very happy to share with you the story of an improbable behavior. Autonomy is the voluntarily break-off of some parts such as a tail or a leg to avoid predation. Indeed this is one of the most extreme and widespread forms of defense founded in nature. Among our robots in particular, a bizarre case of autonomy has been recently described. Males and females of this little scorpion of genus Ananteris are able to break off their tail as a form of defense. This is an unique behavior among scorpions and has been first reported in Colombia, which is my beloved country. But before I tell you more about it, I would like to show you a short video. This is me acting as a predator by pulling the tail of a male of Ananteris. As you can see, the male voluntarily detaches his tail, which twitches automatically for a smooch of 50 seconds after autonomy. So adult scorpions that quickly detach their tails are more likely to survive a predator attack. However, autonomy probably has several consequences for the fitness of tailed scorpions. And I am saying that because when we say tail, we are not talking about the same tails, lizards, salamanders and mammals. What we could contain in scorpions is in fact the posterior parts of their abdomen. This body part is now a metasoma and it contains the posterior end of the digestive, circulatory and nervous system. Moreover, at the end of the tail there is a stinger organ which injects venom in the prey and also the anus. So independently of the break point, individuals are losing important body parts. Few days after tail autonomy, a scar completely blocks the digestive system and because there is no tail regeneration, an individual can never defecate again and suffer from severe constipation for the rest of their lives. To understand the implication of tail autonomy on the locomotion, foraging and reproduction, we have studied the scorpion Ananteris balsani, which inhabits a tropical savanna from São Paulo State in Brazil. Let's start with the locomotor cost. If you want to have access to the paper with all the details of this study, please use this QR code. Well, we know that body mass influences the locomotor performance of the scorpions. In general, lighter individuals are faster than heavier individuals. For instance, females carrying babies on their back are slower than females without babies on their back. Immediately after tail loss in Ananteris, males and females lose nearly 20% of their body mass. So we ask it, do they become faster in the short time? And what about the constipation? We know that males and females keep feeding and since they have lost their anus, their game body mass over time due to prolonged constipation. Thus, we also ask it, do they become slower in the long time? To answer our questions, we film at both tailed and tailed scorpions during a ruin trail. Using the footage, we estimate the maximum running speed of all individuals. The answer to our first question is certainly no. As we can see in this graphic, the maximum running speed is similar between tailed and tailed individuals and the results are the same for males and females. Previous studies on tailed autonomy in lizards have also shown that tailed does not necessarily hamper locomotor performance. It seems that autonomy promotes change in the locomotor performance only when the tail represents a great part of the body mass and this is not the case of Ananteris. The answer to our second question is certainly yes. As we can see in this graphic, after 50 days, there was a marked decrease in the maximum running speed of automatized individuals. Curiously, this pattern was found only for males and not for females. An important implication of this finding is that tailed males are probably more exposed to predation because they get slower and slower over time. So, tailed males probably change their behavior to avoid predation. This change may include foraging in more protected places. Now, let's talk about the possible foraging cause imposed by tailers. To know more about this part of the story, you can access the paper using this QR code. As you all know, scorpions have venom and use it to subdue large prey. However, when the prey is small, scorpions only use their claws. Based on this information, we expected that predation success will decrease after tailed males, especially when the prey is large. Moreover, considering that males are smaller than females, we expected that the negative effects of tailed males will be higher for males than for females. To test our hypothesis, we first recorded the predation success at the time of prey manipulation of tailed individuals. Then we induced tail autonomy in half of these individuals and kept the other half intact. Finally, after one week, we recorded again the predation success at the time of prey manipulation of all individuals. We found that females predation success decreased but not so much after tail autonomy. Moreover, tailed females needed more time to subdue large prey. For males, predation success decreased dramatically from 90% when they were tailed to 17% when they were tailed. Moreover, the time necessary to subdue large prey was much higher for tailed males. In this video, we see a tailed male trying to subdue a large cricket, not that the male tries to use the stinger to inject venom, but there is no tail and no stinger. At the end, the cricket escapes and the male remains without a meal. But there is an interesting side effect of the result. The more the males eat, the more constipated they get. And we now know that in the long term, constipation is bad for the locomotor performance of males. Thus, the decreased ability to capture prey may attenuate the negative effects of constipation for them. Finally, it's time to talk about sex. One more, you can read the full paper using this QR code. And we are going to start with the cause paid by the males. At the first stage of the coarsial behavior, males use the tail to perform a behavior called tail walking. This behavior probably serves as a way to stimulate the female. And at the last stage of the coarship, males also use their tail to support the body during female insemination, which occurs through a small package of sperm. Because tail is important during coarship, we predicted that tailed males would have lower reproductive success than tailed males. To test this hypothesis, we recorded several coarship from tailed and tailed males. Surprisingly, we found that tail loss does not have a negative effect on male reproductive success. The success of the sperm transfer was similar between tailed and tailed males. So, how do tailed males cope with the tail loss? Well, we observed that they also perform the tail wagging with the base of the tail. Moreover, they are able to use the base of the tail to support the body during female insemination. So, even modulated they are efficient lovers. Now, let's see the implications from the female's perspective. Like mammals, female scorpions carry their young within their bodies. Carry them just in case it requires space inside the abdomen, since two objects cannot occupy the same space simultaneously, offspring of tailed females will have less space available for development. Thus, their reproductive success should be lower than tailed females. After insemination, we followed the females for five months until they gave birth. According to our prediction, we found that tailed females produce 29% more offspring than tailed females. Thus, contrary to males, females clearly pay a reproductive cost. Accumulation of issues during five months of pregnancy may leave little space for offspring development and may also impale offspring development due accumulation of toxins. This finding may explain why females are less likely than males though to demise their tail. In conclusion, although the permanent loss of the tail reduces the speed and foraging success of scorpions and even for females reduces the number of offspring, we now know that males and females live long enough to reproduce. Taking together our results provides an explanation for the evolution of one of these bizarre forms of defense. As a final remark, we would like to say that the biodiversity of Neutropical Arthropodsism's medicine and we have much to learn about them. However, if we want to continue to appreciate and study them, we need to preserve the places where they live. Now, we would like to thank a lot of people and institutions that helped and supported us and also all of you for their attention. Thanks.