Remember the folktale about the race between the tortoise and the hare? The hare moved faster, but the slow-moving tortoise reached the finish line first due to his persistence.

The science of movement ecology — born at the Israel Institute for Advanced Studies in 2006 — studies how animals, plants and microorganisms move at various stages of life and in various situations, providing insights for purposes including species conservation.

The father of this scientific discipline, Prof. Ran Nathan, director of the Hebrew University of Jerusalem’s Minerva Center for Movement Ecology, joined students and colleagues from 12 countries in a review of the main wildlife tracking technologies that gather big data on the movements of mammals, birds, fish and other animals in the wild.

The review, published in Science, describes how these technologies work separately and collaboratively to reveal previously unknown information about animal movement, behavior and survival in the wild.

GPS tracking of critically endangered California condors, for instance, provides early alerts to avoid bird collisions with wind turbines.

GPS tracking of albatrosses, meanwhile, can help locate illegal fishing vessels across vast oceans.

Using GPS tracking, Nathan and his students discovered that young vultures from the declining population in Israel climb rising-air columns (thermals) much less efficiently than do experienced adult vultures when those thermals are drifted by winds.

“We found that circling around the core of wind-drifted thermals requires training and patience, likely gained by young vultures only with accumulated experience,” Nathan said.

Novel insights

A new uniquely cost-effective reverse-GPS system called ATLAS, developed by Nathan and Prof. Sivan Toledo of Tel Aviv University and their teams, simultaneously tracks dozens of wild animals with great accuracy at high resolution using small, inexpensive radio tags.

ATLAS has been installed in countries including Israel, the UK, The Netherlands and Germany to answer basic questions in movement ecology. Every day, scientists from Australia to Africa to America are seeking to use ATLAS systems at their study sites, Nathan tells ISRAEL21c.

“This sophisticated tracking system has ushered in a range of exciting discoveries and novel insights, including the first evidence for the existence of a cognitive map in a wild animal — a fruit bat,” said Nathan.

ATLAS facilitated an understanding of how bats instinctively practice “spatial partitioning” among adjacent colonies, and the underlying mechanisms. The bats seem to be driven by spatial memory and information transfer rather than competition.

ATLAS also sparked a pioneering study in the UK linking variation among individual pheasants in their cognitive ability and space-use patterns.

High-resolution data from ATLAS-tracked black-winged kites, which prey on small animals such as voles, revealed “a very large variation in the duration that kites remain static within a food patch, including very short and very long stops, making stop duration rather unpredictable,” Nathan said.

“This might be explained by a predator-prey co-evolution race, in which kites wait until voles get out of their burrows to forage in the fields, while voles minimize exposure in risky times and habitats.”

Fish and bird survival

Another reverse-GPS system, acoustic telemetry, uses acoustic tags to track fish and other aquatic animals in rivers, lakes and seas, yielding new scientific insights and guidelines for dealing with human-inflicted risks.

An acoustic tracking system in European rivers revealed that when endangered downstream-migrating eels and Atlantic salmon encounter dams, their movement becomes more energy intensive and therefore may lower their chances of survival.

Nathan said GPS tracking provided Israeli scientists with an early-warning capacity about the recent avian flu outbreak that led to the death of thousands of migrating cranes in Israel earlier this winter.

“At the first sign of death among a few dozen cranes, a much greater proportion of our GPS-tagged cranes died or were suspected to be infected given the sudden reduction in their movement and activity,” said Nathan.

“We informed the authorities that a drastic mortality event is coming, as unfortunately did happen, and that urgent measures should be taken.”

Later, the team traced the infected birds and found that some eventually recovered.

“We now closely watch the data from cranes that winter in Africa to monitor the possible second wave of the outbreak when millions of migrating birds will soon arrive,” Nathan said.

His lab is working with the Israel Nature and Parks Authority on an early-alert system to find poisoned carcasses that vultures and other raptors are eating.

Nathan says there are four types of research questions that cannot be answered without the highly detailed data the new technologies enable: cognitive and personality variations among individual animals; very brief interactions between members of social groups, competing species or predators and their prey; wildlife interactions with the environment and with humans; and variations in natural phenomena across different scales in time and space.

“We expect our findings to have major implications in both basic and applied research, and to foster a wave of new collaboration across disciplines and political borders. We also foresee a substantial impact beyond our field of research through public environmental awareness and education,” Nathan says.

Produced in association with ISRAEL21c.

Evolution can occur in great leaps, despite Charles Darwin’s theory of evolution by natural selection and small changes over time. Scientists have identified a flower in Colorado dubbed a “hopeful monster,” mutating to adapt to its environment.

“Evolution doesn’t necessarily take all these small changes like Darwin proposed,” Scott Hodges of the University of California-Santa Barbara said of the theory.

Hodges and Zachary Cabin, affiliated with the same university, identified rapid evolutionary change in Colorado blue columbines (Aquilegia coerulea) and a naturally occurring variant, A. coerulea daileyae. The latter lacks the nectar spurs of the former, replacing them with petal-like sepals due to a mutation in a single gene. The two scientists are part of a team that published a study on these findings in the journal Current Biology.

Scientists have long argued over whether evolution plods along for millennia or if it sees sudden, abrupt changes. Large changes in the shape or morphology of species appear in the fossil record within short geological timescales, while intermediate changes may not show up. Researchers have tried to observe the change as it happens to show that sudden developments may drive evolution.

In the study, researchers found a population of Colorado blue columbines was losing petals that feature characteristic nectar spurs. This genetic mutation is not unusual for the species, but spurlessness appears to have become a feature of the area under study: about 25 percent of the plants lack spurs.

The team found that just one gene, APETALA3-3, controls the flower’s spurs and nectaries. “The gene is either on or off, so it’s about as simple of a change [as] you can get,” said Cabin. “But that simple difference causes a radical change in morphology,” he said of the broken gene that causes the loss of petals or nectar spurs.

If these had been fossil specimens, they might have been classified as distinct genera. No intermediate form of the plants would have shown up in the fossil record to show a transition from one to the other. “This finding shows that evolution can occur in a big jump if the right kind of gene is involved,” Hodges said.

APETALA3-3 is a homeotic gene that programs how an organ develops, which can be drastically affected by a mutation. “Most of the mutations of this nature are going to be like that — just awful,” Hodges said, adding that such organisms cannot survive. “Biologist Richard Goldschmidt called them ‘hopeless monsters,’” he said.

Because APETALA3-3 programs an organ to become a petal, “when it’s broken, those instructions aren’t there anymore, and that causes it to develop into a completely different organ — a sepal,” Hodges said.

One of these giant leaps may sometimes yield a trait that is adaptive to a particular environment. This may mean that evolution moves forward in single, large jumps, supportings the punctuated equilibrium hypothesis.

“We did not have a good example of a hopeful monster due to a single genetic change until now,” said Hodges. Other relatives of columbines have also lost petals and nectaries, but scientists had not determined whether the change was gradual or in a giant leap. Because Hodges and Cabin observed this actively happening in a patch of Colorado blue columbines, they can confirm that the bloom is a hopeful monster.

The researchers concluded that the mutation was not mere chance. “To get that many of this mutant type really suggests that there’s selection favoring it somehow,” Hodges said.

He finds it odd because spurs produce nectar and attracts pollinators. But attracting pollinators is only one factor in reproduction. The mutant columbine actually produced more seeds than its counterparts. After checking their data, the authors saw a pattern emerge.

The researchers observed that aphids, caterpillars and deer eat the various versions or morphs of the columbine. While aphids and caterpillars can limit seed production, deer eat and tear up the entire plant. Further data showed that aphids and deer prefer to munch on flowers with nectar spurs.

Change in the morphology of these flowers is usually driven by pollinators, such as hawk moths and bumblebees, but spurlessness appears to be an adaptation to animals consuming the plants. Producing the spurs and nectaries takes a significant amount of energy, according to the study, that can be used instead for producing seeds.

Having identified their hopeful monster, the authors hope to develop a timeline of when the mutations may have occurred and determine how spurlessness is spreading among the flowers.

The Colorado blue columbine may be diverging into separate species, especially since the two types seem to rely on different pollinators. “That splitting process would be slow,” Cabin said, “but there is evidence that it could be on its way.”

“Natural selection can come from very surprising sources. It’s not always what you’d expect it to be,” Hodges said.

Edited by Siân Speakman and Kristen Butler