Research on the memory of turtles
Turtles are a kind of reptiles. Although their number is not large now, in the Mesozoic Era more than 200 million years ago, the number of reptiles on the earth was Very prosperous. By the Triassic period, some reptiles had evolved into mammals and birds. Now most reptiles are extinct, and only a few survive, and the tortoise is one of them (see picture above).
We found that people mostly study the lifespan of tortoises, but few people pay attention to the memory of tortoises. We heard a story: One day in September 1980, Xu Xianping, a villager in Wangdun Village, Zhongzhou Township, Jianli County, Hubei Province, and his brother-in-law caught a big turtle in the creek behind the house. They used a knife to cut the turtle on its back. He engraved his name, punched holes and put on four small copper rings, and then put them back into Dongting Lake. It came back again during the Dragon Boat Festival in 1982, going back and forth like this 8 times.
The same story goes for naturally released sea turtles. After the baby turtles are born, they come to the sea. After a few years, those adult turtles that survive will migrate to the shore accurately every nesting season. They can often migrate to their original specific beaches to nest and lay eggs. . We became interested in this behavior of turtles, so we asked the turtles to walk through the maze to study the memory of the turtles.
Comments
In daily life, we often see or hear a lot of strange things through newspapers, television or other media. For most people. It just aroused a moment of curiosity, but I didn't think about it or thought about it but didn't explore the mystery. The young authors of this topic turned curiosity into action. designed and implemented their experiments while raising questions. The raising of this question has a certain universality and points out an effective way for us to discover problems in the future: starting from some phenomena and special cases in life, discovering the mysteries, and further exploring whether there are universal truths. Being good at discovering and selecting problems is the prerequisite for research-based learning. Research-based learning without problems is meaningless.
For this experiment, we chose the red-eared turtle of the class Reptilia and the genus Turtle, commonly known as the colorful turtle. Most of the turtles sold on the market in our country are this kind of turtle. There is a longitudinal rib on their carapace, which is usually brown or black; the plastron is yellow or brown, and there are dark brown patches on the outer edge of each scute. There are yellow vertical stripes on the sides of the head and neck, and red patches on the ears. The head, neck, tail and limbs can be completely retracted into the shell, making it a very docile turtle. This type of turtle mainly lives in rivers, lakes, swamps or ponds. They live in semi-water, often live in groups, have hibernation habits, like warmth and darkness, and feed on plants, small fish, shrimps, snails, etc. The age and gender of the turtles in this experiment are as follows:
No. Age and Gender
A 3 males
B 2.5 males
C 1.5 Female
D 1 Female
E 1 Male
F 1 Male
Build a maze (see picture below).
There are four lines, of which Road 3 is the main route and Roads 1, 2 and 4 are interference routes. In order to let the turtle know where the exit is, we placed the turtle's nest at the exit. There is plenty of water, food, and warmth there, making the environment suitable for the turtle to live. Let the turtle crawl through the maze once a day.
The situation is as follows:
The first day: A and D turtles walked path 1, C walked path 2, B walked path 3, and F and E took path 4. It takes 35 minutes to 50 minutes and the distance is between 2.5 meters and 3.0 meters.
The next day: Turtles A and B walked path 2, and turtle C took path 4. D and E walked distance 3, and F walked distance 1. The time taken was between 40 and 50 minutes, and the distance was between 2.5 and 3.0 meters.
The third day: B and F walked path 3, A walked path 4, D walked path 2, C and E walked path 1, and then returned to the entrance. It takes between 30 and 35 minutes, and the distance is between 2.5 and 3.0 meters.
Day 4: A and D both chose road 3, which took between 18 minutes and 25 minutes, and the distance ranged between 2.5 meters and 3.0 meters.
The subsequent training data are as follows (average values):
After a period of training, the turtles all remembered the way back to the nest. It takes between 1 minute and 3 minutes.
In order to examine whether the turtle has temporary memory, we conducted a second experiment. As a result, they can find the right path and return to the nest at once. It takes between 10 and 15 minutes.
Two weeks later, a third experiment was conducted on the turtles. As a result, they can find the right path and return to the nest at once.
Comments
After raising the questions to be studied. The young authors further proposed their experimental design: let the turtle walk through the maze. The experimental materials they selected were colorful turtles that are easily available on the market, and they gained an in-depth understanding of the living environment and living habits of colorful turtles. It laid a good foundation for the next experiment. It is not difficult for us to see that the experiment is feasible, which is also something we must pay attention to when conducting research-based learning design experiments. Some students often ignore the feasibility of the topic when choosing a topic. When they start to do the topic, they find that many of the equipment and conditions cannot be met, and they have to start over. This wastes a lot of precious time, and some even end up with no results. end. Therefore, when choosing a topic, you must first consider the feasibility of the topic.
Through experiments, we found that turtles have memory. Because in these days of experiments, as the proportion of turtles choosing the correct route increased, the time it took to get out of the maze also decreased significantly. After observing the brain anatomy of reptiles, we found that the cerebellum of reptiles is relatively developed, as are the cerebral hemispheres and midbrain. New cerebral cortex appears in the cerebral hemispheres. Studies have proven that the neocortex is connected to all senses except smell, and has the function of analyzing, synthesizing, and releasing information. Memory is also an important function of the neocortex. Starting from reptiles, the highest-level centers gradually moved to the neocortex, and the midbrain retreated to the status of lower-level centers. The basal tubercle moves to the inside of the cerebral hemisphere, and the nerve cells of the cerebral cortex move to the surface of the brain. These changes are closely related to their adaptation to the complex environment of real land life.
During a holiday experiment and study, we developed a strong interest in the subject of biology, learned a lot of new knowledge about animals and animal protection, and felt the mystery and complexity of animals. In order to complete this topic, we conducted more than ten experiments during the winter vacation. Through experiments, we feel that the mysteries of biological science are endless. Although we encountered many difficulties during the experiment, everyone worked hard to find solutions to the problems so that the experiment could proceed smoothly. During this period, we learned a lot of knowledge that is not available in books, improved our abilities, enhanced our scientific awareness and spirit of scientific exploration, and cultivated our will to overcome difficulties and our spirit of cooperation.
Comments
The analysis of experimental results must be well-founded and must not be copied mechanically. The conclusion drawn from this experimental design is: turtles have memory. This conclusion is the most direct conclusion drawn from experiments. The young authors did not just stop at this level, but further analyzed the essence of the problem. We know that the structure of living things is adapted to its functions. Based on this theory, the young authors made detailed observations and analysis of the brain structure of reptiles to further deepen their topic. For most students, it is relatively easy to draw direct conclusions from experiments, but this is not enough for a successful research study. What is more important is to discover the essential things from it.