A recent study conducted by the Massachusetts Institute of Technology（MIT）has discovered that river erosion（侵蚀）can lead to increased biodiversity in areas with minimal tectonic（地壳构造的）activity. The researchers focused their attention on the Tennessee River Basin and examined how the erosion of various rock types by the river had led to the separation and diversification of a type of fish called the greenfin darter. As time passed, these separate fish populations evolved into distinct families with genetic differences.

Scientist Thomas Near observed that the greenfin darter was exclusively found in the southern half of the Tennessee River Basin. The researchers analyzed the genes of each fish in Near's data set and constructed an evolutionary tree. This tree helped them comprehend the evolution and differences of the greenfin darter species. They discovered that the fish within the same branch of the river were more closely related to each other than to the fish in other branches.

This study provides evidence that river erosion significantly impacts biodiversity in regions with low tectonic activity. It illustrates how changes in the landscape caused by river erosion can lead to the division and diversification of species over time, even in peaceful environments. These findings enhance our understanding of the mechanisms（机制）that drive biodiversity and evolution, even in areas that are not typically associated with intense tectonic activity.

Subsequently, the team discovered a strong correlation between the habitats of the greenfin darter and the type of rocks present. The southern half of the Tennessee River Basin consists of hard, tightly packed rocks, resulting in turbulent（湍急的）waves in the rivers that flow through it. This characteristic may be favored by the greenfin darter. As a result, the team assumed whether the distribution of greenfin darter habitats had been influenced by the changing rock types, as the rivers eroded the land over time. To test this assumption, the researchers developed a simulation model. Remarkably, the results confirmed their assumption.

Photos a recent California college graduate took with her parents in the fields where they worked as migrant farm laborers went viral this week, after her school shared the images and the story of her journey on the Facebook page.

Jessica Rocha graduated from the University of California, San Diego, with a degree in sociology on Saturday. In the post, Rocha said her parents came from Michoacan, Mexico, and that while she was growing up, they had her work in the fields alongside them.

She started working in the fields in high school after classes. "I admired the workers because they kept working despite backaches while files, mosquitos and bugs kept roaming their faces, getting into their eyes," she said," Nobody thinks about nor sees what happens behind a vegetable you grab at the grocery store. But behind it is someone who breaks their backs every day working in the fields. "

She continued to work in the fields on weekends and school breaks even after she left for college and had a job with the University of California Police Department. She credited her parents. "Many times I wanted to give up, but my parents and their pieces of advice and support were the reason I kept going," Rocha said." If it wasn't for how my parents raised me, I don't know who I would be today," she added," Working in the fields builds a different type of character, a character that does not give up, and one with resilience (韧性) and strength to face challenges."

I became aware of my stutter (结巴) when I was around 9, in the fourth grade. I began to see how other people viewed me. When the teacher asked the whole class questions, I never raised my hand though I knew the answer, because I knew I would stutter. Some kids would tell me that I talked funny, ask why I didn't talk normally, or laugh at me. As soon as that started to happen, I became more introverted (内向的).

It wasn't until the summer of 2015, before freshman year at high school. All my friends and my parents encouraged me to join the high school football team. I owed much to them, especially Coach Lane who taught me how to play football. He took the time-and had the patience-to actually teach me what to do, how to do it and how to understand the concepts of play.

In junior year, I started my first game for the high school team. I had a very good season and in January 2018, I signed the University of North Carolina. The older we get, the more of an understanding we have about the world and other people. So the first time my teammates in college heard me talk and heard that I stuttered, they did not say a thing. That was a big deal to me because I was so used to people making comments. My teammates actually tell me to slow down because talking faster causes me to stutter more. It's really helped me develop confidence.

Whenever I go back home to Georgia, I volunteer with children at my church, including those who have learning disabilities. I like to do that to inspire them with confidence. I had confidence issues when I was a kid because of my stutter, so I just don't want them to have to go through what I did. In the future, I would like to start a foundation to give back to people who stutter and create a program where kids all across the world who have a stutter can have a safe space.