Amid a tropical paradise known as ‘Lizard Island,’ researchers are cracking open evolution’s black box – scientist at work

Every morning in Miami, our field work begins in the same way. Fresh Cuban coffee and pastelitos – delicious Latin pastries – nourish our team for another day of evolutionary detectives. Here we follow the development in actual time, and measure natural selection as it happens in a society of Caribbean lizards.

as assistant professor From the environment and development in Georgia TechnologyMy journey took me with these wonderful reptiles Away from my roots in London. The warm air and moisture in Miami feels that it is normal now, and it is far from the gray streets and the lid and free from the lizard in my British upbringing.

Our research is taking place on the island of South Florida almost the size of an American football field – assuming that we are successful in avoiding US crocodiles that sunn away in the surrounding lake. We call it the island of the lizard, which is a special place.

Here, since 2015, we are conducting evolutionary research on five types of Wonderful lizards are called Anols. By studying Anols, our team is working to understand one of the basic questions in biology: How leads to natural selection developing in actual time?

Every May, In conjunction with the beginning of the breeding seasonWe visit Island Lizard to pick up, study and release all the affairs of adults – a population that fluctuates between 600 to 1000. Throughout the entire summer, females put one egg every seven to 10 days. By October, a completely new generation appeared.

The secret life of lizards

ANOLS is not an early emerging, so we do not expect much activity until the sun is strengthened around 9:30 am; This gives us time to prepare our equipment. Our team holds the telescopic fishing poles equipped with small series, which we use to gently detonate lizards from the branches and tree trunks. Ask any lizard biologist about Their favorite laso materials Will it provoke the old discussion: hunting line or tooth thread? When it is worth, we recently turned it – we are now on the team hunting line.

Imagine yourself as Anole on the island of Al -Sahliya. Your life is short – usually only one year – full of daily challenges. You need to warm up in the sun, find enough food to survive, search for a companion, guard your favorite branch from other lizards and avoid eating it by the predator.

Like humans, every lizard is unique. Some have longer legs, others are stronger jaws, all of which behave slightly differently. These differences can determine who remains and not; Who has most children and not.

These results are an engine Development by natural selectionThe process in which organisms with the appropriate features of their environment tend to survive and reproduce more. Then these beneficial features are transferred to future generations, and the species gradually change over time. However, scientists still have an incomplete understanding of how each of these features predicts the winners and losers in life in the wilderness.

To understand how species evolve, researchers need to open this black square of development and investigate natural selection in land groups. My colleagues and I do this by studying ANOLS in great details. Last year was particularly exciting: We ran what we called the Charmish Olympics.

Small hunting columns

When you build the morning heat, we have discovered our first lizards: Cuban brown nicknames near the ground, and the inherited standards of Anols Hispaniaolan banoles directly above it. Moreover, in lush tree umbrellas, there are American green, and the largest species, the Cuban knight, the size of a newborn cat.

In 2018, a new competitor entered the arena – Portorico Crod Anul, a type already in Miami but has not yet reached Lyzard Island. It allowed us to reach an unexpected opportunity to study how species evolve in actual time In response to a new neighbor.

Hunting these athletes requires graceful patience and accuracy. Through our modified fishing poles, we carefully shave the tooth thread on their heads. Each site features a bright pink tape and a unique identifier; Then all lizards are transferred to our field laboratory shortly on foot.

Lizard Olympics

Here, real Olympic trials begin. Each athlete passes with a comprehensive evaluation. Our portable X -ray machine unveils the structure of the skeleton, and the high -resolution scannings pick up the complex details of their feet. This is very important: Like the cousins ​​of JikoAnols has a wonderful sticky fingers that allow them to cling to softening surfaces like leaves and Perhaps even survival hurricanes.

We also measure the shape and claws, because both features are two decisive things for the climbers. DNA samples provide a genetic imprint for each individual, allowing us to set family relations across the island and know what is the most successful.

Performance experiences are where things become interesting. Imagine a small path meeting with the lizards. Using high -speed video cameras, we test the speed of operation of each lizard, and the use of specialized equipment that measures the difficulty of the sting and the strength of the harsh branches and soft leaves.

These are not arbitrary measurements – each of which represents a possible developmental advantage. The fast lizards may escape the predators better. Strong bites may determine the winners of regional conflicts. Excellent fist is very important for sparkles the umbrella of the trees.

Each measurement helps us answer the basic questions about development: Does the fastest lizards live longer? Do you produce the most powerful Biters more offspring? These are the basic measures of development by natural selection.

As the afternoon approaching, the team takes each piece of bright pink ribbon and restores the corresponding lizard to the arrested branch. Anols now owns two small signs 3 millimeters with a unique symbol that allows us to get to know it when we return it on future research trips, along with a small group of white nail polish until we know not to capture it immediately after we let it go.

At 8:30 pm, with the lizard Olympics that were made for today, we return to the island raised the headlights. A night brings a different perspective. It is difficult to pick up some of the most vibrant lizards when shipping completely through the midday sun, so our night novels allow us to find them during sleep. However, it is often racing with time. The corn snakes that eat hungry lizard are also hunting, trying to find the sides before we do so. While we conclude another day for 16 hours around 11:30 pm, the team shares night stories.

Developed

It now extends 10 years, 10 generations and five types. One of the longest active studies Its kind in evolutionary biology. By tracking individuals who live and reproduce it, and link their success with specific material features and performance capabilities, we document natural selection with unprecedented details.

So far we have discovered two great patterns. Initially, he did not pay to be different on the island of al -Soriya. ANOLS with very medium shapes and sizes lived for a longer period compared to Those that differ a little. But when the crowned Anols arrived, everything changed: suddenly, comprehensive brown with longer legs It was the feature to survive.

Lizard Olympics helps us understand the cause. The largest and most aggressive roles that are forced on Brown tissue to spend more time on the ground, as those who have longer legs to escape from predators-which allows them to better stay on long leg genes, may run, while genes with shorter legs may be eaten before they can reproduce them.

By watching natural selection, a response to environmental changes is revealed, instead of concluding from fossil records, we provide advanced evidence of the evolutionary processes that Charles Darwin can only be seen.

These long days of observation slowly reveal one of the basic operations in biology. Each lizard we pick up, each measurement of it adds another piece to our understanding of how to adapt species and develop in a constantly changing world.

This article has been republished from ConversationAn independent, non -profit news organization brings you facts and trusted analysis to help you understand our complex world. Written by: James T. Strokeand Georgia Institute of Technology

Read more:

James T