International Journal of Molecular Ecology and Conservation, 2025, Vol.15, No.4, 196-205 http://ecoevopublisher.com/index.php/ijmec 19 8 2.2 Life history and reproductive capacity The life cycle of the African land snail is characterized by a high reproduction rate, and it grows rapidly at each stage of its life cycle. The individual is hermaphroditic, and the same individual has both male and female reproductive organs. Usually, two individuals mate to increase genetic diversity, but self-fertilization reproduction can also occur in the absence of a mate (Ramdwar et al., 2024). The breeding season is almost uninterrupted throughout the year and is particularly active in warm and humid conditions (De Almeida, 2013). Each adult snail can lay hundreds or even thousands of eggs in a year. Studies have shown that in an ideal environment, A single A. fulica can lay 200 to 1,800 eggs per year, and the hatching survival rate of the eggs can reach 90% (Sika et al., 2023). In terms of lifespan, the lifespan of the East African giant snail in the wild is generally 3 to 5 years, and it can reach 8 to 9 years under captivity conditions (Ramdwar et al., 2024). The combination of high reproductive capacity and long lifespan makes it difficult for its population to naturally decline once it is established. Especially in invasive areas lacking the restraint of natural enemies, the population size often grows exponentially, exerting continuous pressure on the local ecology and agricultural system. This "r countermeasure" style of life history is precisely the key reason why it has become an invasive pest. 2.3 Ecological adaptability One of the key reasons why the African land snail has successfully invaded many places lies in its wide ecological adaptability. This species has a relatively wide tolerance range for temperature and humidity. Research reports: A. fulica's most suitable activity temperature is 15-38℃, and soil moisture is 45%~85% (Albuquerque et al., 2009). In the tropical regions where the temperature and humidity are high all year round, snails are almost active and reproduce throughout the year. A. fulica is not picky about food resources and shows A broad appetite. Its diet includes young leaves, fruits, bark, flowers, vegetables, as well as humus, moss, fungi, etc. (Santos et al., 2018). This diverse feeding ability means that no matter what kind of plants the invaded area provides, it almost always has means to utilize them. The adaptability of A. Fulica is also reflected in its tolerance to pollution and diseases. Studies have found that its intestinal flora has a certain tolerance to heavy metals and antibiotics, enabling it to survive in urban polluted environments. More notably, climate warming is expanding its potential distribution area (Guo et al., 2019). Model predictions show that against the backdrop of global warming, the originally overly cold temperate regions will partially become suitable for A. fulica to survive. However, this snail still cannot survive for a long time in extremely low temperatures, and the continuous freezing climate will cause its death. This to some extent restricts its diffusion to higher latitudes. 3 Invasion Routes and Transmission Mechanisms 3.1 Communication driven by human activities Human intentional or unintentional behavior is the primary factor for the cross-regional spread of land snails in Africa. Historically, many long-distance transmissions of this species have been directly attributed to human activities. In agricultural and horticultural routes, during international agricultural product trade and the transportation of plant seedlings, snails and their eggs are often carried and spread as "pollutants". Another example is the intentional introduction and release: In some regions, the East African giant snail was once regarded as a potential food source or commercial breeding target, and was introduced for use in meat protein, medicine, etc. (Sarma et al., 2015; Goldyn et al., 2016). Furthermore, snails or eggs can migrate over long distances by hiding in the crevices of transportation vehicles such as containers, vehicle tires, and cargo ship ballast (Vijayan et al., 2022). During World War II in history, the Japanese army carried A. fulica as A food source on the Pacific battlefield. After the war, these snails escaped into the local area and then spread. 3.2 Natural diffusion mechanism In addition to long-distance cross-border transmission, in the local areas where the invasion occurs, the African land snail can also naturally spread by relying on its own ability or environmental media. A. fulica has A certain ability of active crawling and diffusion. Although adult snails move slowly, they can move at a speed of about 1 to
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