Gorillas (大猩猩) in films such as King Kong and Tarzan are wildly beating their chests when under threat. Researchers have tried to find out what the behavior might mean, and they doubt that the gorillas exhibit this behavior not to start fights, but to prevent themselves — and chest-beating could be used to advertise (展示) their body size to other gorillas.

Scientists observed 25 wild male mountain gorillas for over 3,000 hours. The research team used audio (音频) equipment to record the sound frequency (频率), rate, duration, and amount of chest beats. To determine each gorilla’s size, the researchers used cameras to photogragh and measure each gorilla’s back.

Although the rate, duration, and amount of beats did not correlate (相关) with the size of the gorillas, sound frequency did , the researchers report. The team also noticed that larger gorillas produced deeper-tone chest drumming. Previous research has shown that a gorilla’s larger body size is linked to reproductive success and social rank (地位). The chest-beating could be a way for the gorillas to advertise their size to others and, in turn, avoid fights that could result in serious injury or death.

Though gorillas can obviously observe size just by getting a good look at others, the researchers suggest chest beating is copper-bottomed when trying to communicate through a thick forest. The sounds gorillas created by beating their chests are powerful enough to travel long distance through thick forests and signal others their size and fighting ability.

Animal expert Anna Nekaris says it would be interesting to see if smaller gorillas can imitate the deep tones of larger ones in future studies. Nekaris says, “For now, the researchers will continue to study chest-beating to see if the action can pass on other information, such as dominance rank (优势等级), sex, and individual identity, to nearby gorillas.”

International Horticultural Exhibition 2019 Beijing China

According to official statistics, over 110 nations and international organizations, over 120 unofficial exhibitors, as well as 31 Chinese provinces, autonomous regions and municipalities, together with Hong Kong, Macao and Taiwan have established gardens in the Expo Park, each presenting their own distinctive gardening and horticulture(园艺学).

Main scenic spots include: Core Scenic Area --- International Pavilion(展馆), China Pavilion, Plant Pavilion, Horticultural Experience Pavilion and Guirui Theater, 12 typical sites, International Horticulture, Chinese Landscape Horticulture, Horticultural Industry Development Belt, Great Master’s Garden, and Special Gardens.

The Exhibition started on April 29 and will end on October 7, 2019, lasting for 162 days and spanning three seasons including spring, summer and fall.

According to the International Exhibitions Bureau, the world exposition can be divided into two major categories based on their nature, scale and duration(持续时间). One is international registered exhibitions, which are also the highest level of expos globally, such as the Shanghai World Expo 2010. The other is the international recognized exhibitions or specialized expos, such as the International Horticultural Exhibition 2019.

The International Horticultural Exhibition (A1) is a horticultural exhibition of the highest level and greatest influence with AIPH’s approval and Bureau of International Exposition’s recognition. Beijing is the second Chinese city to hold the A1-level exhibition following Kunming in Yunnan Province. Cities in the following countries have also held the highest-level expo in the world: the Netherlands, Austria, Germany, France, Canada, the U.K., Japan, Thailand and Turkey. Among them, the Netherlands has held six A1 exhibitions since 1960, followed by Germany, five.

It would be easy to think that since houseplants live inside , they don’t really experience seasons as their outdoor relatives do. It’s true that they’re provided a lot more protection inside. 【小题1】They do，they do and they’d appreciate a few seasonal changes. Here is how to keep your plants happy as the summer goes away and cooler days come along.

If you’ve given your houseplants outside time in summer , bring them in before temperatures reach a low of 55 degrees Fahrenheit.【小题2】 For example, clear the dead leaves, which can attract pests. In this way, you won’t bring in whatever may be harmful to your indoor environment.

【小题3】Fall is the perfect time to leach out(滤掉)any salt by letting the water run freely out of the bottom of the pot. The water will also clean off any dust that collects on the leaves.

Give them a trim( 修剪). Remove any dead or dying leaves ：cut the leaves that are brown or yellow at the base. For brown or yellowing tips, you can just cut off the unhealthy leaves. 【小题4】

Be mindful of extreme temperatures. Being extremely hot or cold can stress plants out. 【小题5】Make sure they aren’t on the top of radiators(散热器)or by heaters; likewise, make sure they’re far from doors that are open to the outside.