More on Personal Growth
Matthew Royse
3 years ago
7 ways to improve public speaking
How to overcome public speaking fear and give a killer presentation
"Public speaking is people's biggest fear, according to studies. Death's second. The average person is better off in the casket than delivering the eulogy." — American comedian, actor, writer, and producer Jerry Seinfeld
People fear public speaking, according to research. Public speaking can be intimidating.
Most professions require public speaking, whether to 5, 50, 500, or 5,000 people. Your career will require many presentations. In a small meeting, company update, or industry conference.
You can improve your public speaking skills. You can reduce your anxiety, improve your performance, and feel more comfortable speaking in public.
“If I returned to college, I'd focus on writing and public speaking. Effective communication is everything.” — 38th president Gerald R. Ford
You can deliver a great presentation despite your fear of public speaking. There are ways to stay calm while speaking and become a more effective public speaker.
Seven tips to improve your public speaking today. Let's help you overcome your fear (no pun intended).
Know your audience.
"You're not being judged; the audience is." — Entrepreneur, author, and speaker Seth Godin
Understand your audience before speaking publicly. Before preparing a presentation, know your audience. Learn what they care about and find useful.
Your presentation may depend on where you're speaking. A classroom is different from a company meeting.
Determine your audience before developing your main messages. Learn everything about them. Knowing your audience helps you choose the right words, information (thought leadership vs. technical), and motivational message.
2. Be Observant
Observe others' speeches to improve your own. Watching free TED Talks on education, business, science, technology, and creativity can teach you a lot about public speaking.
What worked and what didn't?
What would you change?
Their strengths
How interesting or dull was the topic?
Note their techniques to learn more. Studying the best public speakers will amaze you.
Learn how their stage presence helped them communicate and captivated their audience. Please note their pauses, humor, and pacing.
3. Practice
"A speaker should prepare based on what he wants to learn, not say." — Author, speaker, and pastor Tod Stocker
Practice makes perfect when it comes to public speaking. By repeating your presentation, you can find your comfort zone.
When you've practiced your presentation many times, you'll feel natural and confident giving it. Preparation helps overcome fear and anxiety. Review notes and important messages.
When you know the material well, you can explain it better. Your presentation preparation starts before you go on stage.
Keep a notebook or journal of ideas, quotes, and examples. More content means better audience-targeting.
4. Self-record
Videotape your speeches. Check yourself. Body language, hands, pacing, and vocabulary should be reviewed.
Best public speakers evaluate their performance to improve.
Write down what you did best, what you could improve and what you should stop doing after watching a recording of yourself. Seeing yourself can be unsettling. This is how you improve.
5. Remove text from slides
"Humans can't read and comprehend screen text while listening to a speaker. Therefore, lots of text and long, complete sentences are bad, bad, bad.” —Communications expert Garr Reynolds
Presentation slides shouldn't have too much text. 100-slide presentations bore the audience. Your slides should preview what you'll say to the audience.
Use slides to emphasize your main point visually.
If you add text, use at least 40-point font. Your slides shouldn't require squinting to read. You want people to watch you, not your slides.
6. Body language
"Body language is powerful." We had body language before speech, and 80% of a conversation is read through the body, not the words." — Dancer, writer, and broadcaster Deborah Bull
Nonverbal communication dominates. Our bodies speak louder than words. Don't fidget, rock, lean, or pace.
Relax your body to communicate clearly and without distraction through nonverbal cues. Public speaking anxiety can cause tense body language.
Maintain posture and eye contact. Don’t put your hand in your pockets, cross your arms, or stare at your notes. Make purposeful hand gestures that match what you're saying.
7. Beginning/ending Strong
Beginning and end are memorable. Your presentation must start strong and end strongly. To engage your audience, don't sound robotic.
Begin with a story, stat, or quote. Conclude with a summary of key points. Focus on how you will start and end your speech.
You should memorize your presentation's opening and closing. Memorize something naturally. Excellent presentations start and end strong because people won't remember the middle.
Bringing It All Together
Seven simple yet powerful ways to improve public speaking. Know your audience, study others, prepare and rehearse, record yourself, remove as much text as possible from slides, and start and end strong.
Follow these tips to improve your speaking and audience communication. Prepare, practice, and learn from great speakers to reduce your fear of public speaking.
"Speaking to one person or a thousand is public speaking." — Vocal coach Roger Love
Matthew Royse
3 years ago
These 10 phrases are unprofessional at work.
Successful workers don't talk this way.

"I know it's unprofessional, but I can't stop." — Author Sandy Hall
Do you realize your unprofessionalism? Do you care? Self-awareness?
Everyone can improve their unprofessionalism. Some workplace phrases and words shouldn't be said.
People often say out loud what they're thinking. They show insecurity, incompetence, and disrespect.
"Think before you speak," goes the saying.
Some of these phrases are "okay" in certain situations, but you'll lose colleagues' respect if you use them often.
Your word choice. Your tone. Your intentions. They matter.
Choose your words carefully to build work relationships and earn peer respect. You should build positive relationships with coworkers and clients.
These 10 phrases are unprofessional.
1. That Meeting Really Sucked
Wow! Were you there? You should be responsible if you attended. You can influence every conversation.
Alternatives
Improve the meeting instead of complaining afterward. Make it more meaningful and productive.
2. Not Sure if You Saw My Last Email
Referencing a previous email irritates people. Email follow-up can be difficult. Most people get tons of emails a day, so it may have been buried, forgotten, or low priority.
Alternatives
It's okay to follow up, but be direct, short, and let the recipient "save face"
3. Any Phrase About Sex, Politics, and Religion
Discussing sex, politics, and religion at work is foolish. If you discuss these topics, you could face harassment lawsuits.
Alternatives
Keep quiet about these contentious issues. Don't touch them.
4. I Know What I’m Talking About
Adding this won't persuade others. Research, facts, and topic mastery are key to persuasion. If you're knowledgeable, you don't need to say this.
Alternatives
Please don’t say it at all. Justify your knowledge.
5. Per Our Conversation
This phrase sounds like legal language. You seem to be documenting something legally. Cold, stern, and distant. "As discussed" sounds inauthentic.
Alternatives
It was great talking with you earlier; here's what I said.
6. Curse-Word Phrases
Swearing at work is unprofessional. You never know who's listening, so be careful. A child may be at work or on a Zoom or Teams call. Workplace cursing is unacceptable.
Alternatives
Avoid adult-only words.
7. I Hope This Email Finds You Well
This is a unique way to wish someone well. This phrase isn't as sincere as the traditional one. When you talk about the email, you're impersonal.
Alternatives
Genuinely care for others.
8. I Am Really Stressed
Happy, strong, stress-managing coworkers are valued. Manage your own stress. Exercise, sleep, and eat better.
Alternatives
Everyone has stress, so manage it. Don't talk about your stress.
9. I Have Too Much to Do
You seem incompetent. People think you can't say "no" or have poor time management. If you use this phrase, you're telling others you may need to change careers.
Alternatives
Don't complain about your workload; just manage it.
10. Bad Closing Salutations
"Warmly," "best," "regards," and "warm wishes" are common email closings. This conclusion sounds impersonal. Why use "warmly" for finance's payment status?
Alternatives
Personalize the closing greeting to the message and recipient. Use "see you tomorrow" or "talk soon" as closings.
Bringing It All Together
These 10 phrases are unprofessional at work. That meeting sucked, not sure if you saw my last email, and sex, politics, and religion phrases.
Also, "I know what I'm talking about" and any curse words. Also, avoid phrases like I hope this email finds you well, I'm stressed, and I have too much to do.
Successful workers communicate positively and foster professionalism. Don't waste chances to build strong work relationships by being unprofessional.
“Unprofessionalism damages the business reputation and tarnishes the trust of society.” — Pearl Zhu, an American author
This post is a summary. Read full article here

Daniel Vassallo
3 years ago
Why I quit a $500K job at Amazon to work for myself
I quit my 8-year Amazon job last week. I wasn't motivated to do another year despite promotions, pay, recognition, and praise.
In AWS, I built developer tools. I could have worked in that field forever.
I became an Amazon developer. Within 3.5 years, I was promoted twice to senior engineer and would have been promoted to principal engineer if I stayed. The company said I had great potential.
Over time, I became a reputed expert and leader within the company. I was respected.
First year I made $75K, last year $511K. If I stayed another two years, I could have made $1M.
Despite Amazon's reputation, my work–life balance was good. I no longer needed to prove myself and could do everything in 40 hours a week. My team worked from home once a week, and I rarely opened my laptop nights or weekends.
My coworkers were great. I had three generous, empathetic managers. I’m very grateful to everyone I worked with.
Everything was going well and getting better. My motivation to go to work each morning was declining despite my career and income growth.
Another promotion, pay raise, or big project wouldn't have boosted my motivation. Motivation was also waning. It was my freedom.
Demotivation
My motivation was high in the beginning. I worked with someone on an internal tool with little scrutiny. I had more freedom to choose how and what to work on than in recent years. Me and another person improved it, talked to users, released updates, and tested it. Whatever we wanted, we did. We did our best and were mostly self-directed.
In recent years, things have changed. My department's most important project had many stakeholders and complex goals. What I could do depended on my ability to convince others it was the best way to achieve our goals.
Amazon was always someone else's terms. The terms started out simple (keep fixing it), but became more complex over time (maximize all goals; satisfy all stakeholders). Working in a large organization imposed restrictions on how to do the work, what to do, what goals to set, and what business to pursue. This situation forced me to do things I didn't want to do.
Finding New Motivation
What would I do forever? Not something I did until I reached a milestone (an exit), but something I'd do until I'm 80. What could I do for the next 45 years that would make me excited to wake up and pay my bills? Is that too unambitious? Nope. Because I'm motivated by two things.
One is an external carrot or stick. I'm not forced to file my taxes every April, but I do because I don't want to go to jail. Or I may not like something but do it anyway because I need to pay the bills or want a nice car. Extrinsic motivation
One is internal. When there's no carrot or stick, this motivates me. This fuels hobbies. I wanted a job that was intrinsically motivated.
Is this too low-key? Extrinsic motivation isn't sustainable. Getting promoted felt good for a week, then it was over. When I hit $100K, I admired my W2 for a few days, but then it wore off. Same thing happened at $200K, $300K, $400K, and $500K. Earning $1M or $10M wouldn't change anything. I feel the same about every material reward or possession. Getting them feels good at first, but quickly fades.
Things I've done since I was a kid, when no one forced me to, don't wear off. Coding, selling my creations, charting my own path, and being honest. Why not always use my strengths and motivation? I'm lucky to live in a time when I can work independently in my field without large investments. So that’s what I’m doing.
What’s Next?
I'm going all-in on independence and will make a living from scratch. I won't do only what I like, but on my terms. My goal is to cover my family's expenses before my savings run out while doing something I enjoy. What more could I want from my work?
You can now follow me on Twitter as I continue to document my journey.
This post is a summary. Read full article here
You might also like

Alex Mathers
25 years ago
400 articles later, nobody bothered to read them.
Writing for readers:
14 years of daily writing.
I post practically everything on social media. I authored hundreds of articles, thousands of tweets, and numerous volumes to almost no one.
Tens of thousands of readers regularly praise me.
I despised writing. I'm stuck now.
I've learned what readers like and what doesn't.
Here are some essential guidelines for writing with impact:
Readers won't understand your work if you can't.
Though obvious, this slipped me up. Share your truths.
Stories engage human brains.
Showing the journey of a person from worm to butterfly inspires the human spirit.
Overthinking hinders powerful writing.
The best ideas come from inner understanding in between thoughts.
Avoid writing to find it. Write.
Writing a masterpiece isn't motivating.
Write for five minutes to simplify. Step-by-step, entertaining, easy steps.
Good writing requires a willingness to make mistakes.
So write loads of garbage that you can edit into a good piece.
Courageous writing.
A courageous story will move readers. Personal experience is best.
Go where few dare.
Templates, outlines, and boundaries help.
Limitations enhance writing.
Excellent writing is straightforward and readable, removing all the unnecessary fat.
Use five words instead of nine.
Use ordinary words instead of uncommon ones.
Readers desire relatability.
Too much perfection will turn it off.
Write to solve an issue if you can't think of anything to write.
Instead, read to inspire. Best authors read.
Every tweet, thread, and novel must have a central idea.
What's its point?
This can make writing confusing.
️ Don't direct your reader.
Readers quit reading. Demonstrate, describe, and relate.
Even if no one responds, have fun. If you hate writing it, the reader will too.
INTΞGRITY team
3 years ago
Privacy Policy
Effective date: August 31, 2022
This Privacy Statement describes how INTΞGRITY ("we," or "us") collects, uses, and discloses your personal information. This Privacy Statement applies when you use our websites, mobile applications, and other online products and services that link to this Privacy Statement (collectively, our "Services"), communicate with our customer care team, interact with us on social media, or otherwise interact with us.
This Privacy Policy may be modified from time to time. If we make modifications, we will update the date at the top of this policy and, in certain instances, we may give you extra notice (such as adding a statement to our website or providing you with a notification). We encourage you to routinely review this Privacy Statement to remain informed about our information practices and available options.
INFORMATION COLLECTION
The Data You Provide to Us
We collect information that you directly supply to us. When you register an account, fill out a form, submit or post material through our Services, contact us via third-party platforms, request customer assistance, or otherwise communicate with us, you provide us with information directly. We may collect your name, display name, username, bio, email address, company information, your published content, including your avatar image, photos, posts, responses, and any other information you voluntarily give.
In certain instances, we may collect the information you submit about third parties. We will use your information to fulfill your request and will not send emails to your contacts unrelated to your request unless they separately opt to receive such communications or connect with us in some other way.
We do not collect payment details via the Services.
Automatically Collected Information When You Communicate with Us
In certain cases, we automatically collect the following information:
We gather data regarding your behavior on our Services, such as your reading history and when you share links, follow users, highlight posts, and like posts.
Device and Usage Information: We gather information about the device and network you use to access our Services, such as your hardware model, operating system version, mobile network, IP address, unique device identifiers, browser type, and app version. We also collect information regarding your activities on our Services, including access times, pages viewed, links clicked, and the page you visited immediately prior to accessing our Services.
Information Obtained Through Cookies and Comparable Tracking Technologies: We collect information about you through tracking technologies including cookies and web beacons. Cookies are little data files kept on your computer's hard disk or device's memory that assist us in enhancing our Services and your experience, determining which areas and features of our Services are the most popular, and tracking the number of visitors. Web beacons (also known as "pixel tags" or "clear GIFs") are electronic pictures that we employ on our Services and in our communications to assist with cookie delivery, session tracking, and usage analysis. We also partner with third-party analytics providers who use cookies, web beacons, device identifiers, and other technologies to collect information regarding your use of our Services and other websites and applications, including your IP address, web browser, mobile network information, pages viewed, time spent on pages or in mobile apps, and links clicked. INTΞGRITY and others may use your information to, among other things, analyze and track data, evaluate the popularity of certain content, present content tailored to your interests on our Services, and better comprehend your online activities. See Your Options for additional information on cookies and how to disable them.
Information Obtained from Outside Sources
We acquire information from external sources. We may collect information about you, for instance, through social networks, accounting service providers, and data analytics service providers. In addition, if you create or log into your INTΞGRITY account via a third-party platform (such as Apple, Facebook, Google, or Twitter), we will have access to certain information from that platform, including your name, lists of friends or followers, birthday, and profile picture, in accordance with the authorization procedures determined by that platform.
We may derive information about you or make assumptions based on the data we gather. We may deduce your location based on your IP address or your reading interests based on your reading history, for instance.
USAGE OF INFORMATION
We use the information we collect to deliver, maintain, and enhance our Services, including publishing and distributing user-generated content, and customizing the posts you see. Additionally, we utilize collected information to: create and administer your INTΞGRITY account;
Send transaction-related information, including confirmations, receipts, and user satisfaction surveys;
Send you technical notices, security alerts, and administrative and support messages;
Respond to your comments and queries and offer support;
Communicate with you about new INTΞGRITY content, goods, services, and features, as well as other news and information that we believe may be of interest to you (see Your Choices for details on how to opt out of these communications at any time);
Monitor and evaluate usage, trends, and activities associated with our Services;
Detect, investigate, and prevent security incidents and other harmful, misleading, fraudulent, or illegal conduct, and safeguard INTΞGRITY’s and others' rights and property;
Comply with our legal and financial requirements; and Carry out any other purpose specified to you at the time the information was obtained.
SHARING OF INFORMATION
We share personal information where required by law or as otherwise specified in this policy:
Personal information is shared with other Service users. If you use our Services to publish content, make comments, or send private messages, for instance, certain information about you, such as your name, photo, bio, and other account information you may supply, as well as information about your activity on our Services, will be available to others (e.g., your followers and who you follow, recent posts, likes, highlights, and responses).
We share personal information with vendors, service providers, and consultants who require access to such information to perform services on our behalf, such as companies that assist us with web hosting, storage, and other infrastructure, analytics, fraud prevention, and security, customer service, communications, and marketing.
We may release personally identifiable information if we think that doing so is in line with or required by any relevant law or legal process, including authorized demands from public authorities to meet national security or law enforcement obligations. If we intend to disclose your personal information in response to a court order, we will provide you with prior notice so that you may contest the disclosure (for example, by seeking court intervention), unless we are prohibited by law or believe that doing so could endanger others or lead to illegal conduct. We shall object to inappropriate legal requests for information regarding users of our Services.
If we believe your actions are inconsistent with our user agreements or policies, if we suspect you have violated the law, or if we believe it is necessary to defend the rights, property, and safety of INTΞGRITY, our users, the public, or others, we may disclose your personal information.
We share personal information with our attorneys and other professional advisers when necessary for obtaining counsel or otherwise protecting and managing our business interests.
We may disclose personal information in conjunction with or during talks for any merger, sale of corporate assets, financing, or purchase of all or part of our business by another firm.
Personal information is transferred between and among INTΞGRITY, its current and future parents, affiliates, subsidiaries, and other companies under common ownership and management.
We will only share your personal information with your permission or at your instruction.
We also disclose aggregated or anonymized data that cannot be used to identify you.
IMPLEMENTATIONS FROM THIRD PARTIES
Some of the content shown on our Services is not hosted by INTΞGRITY. Users are able to publish content hosted by a third party but embedded in our pages ("Embed"). When you interact with an Embed, it can send information to the hosting third party just as if you had visited the hosting third party's website directly. When you load an INTΞGRITY post page with a YouTube video Embed and view the video, for instance, YouTube collects information about your behavior, such as your IP address and how much of the video you watch. INTΞGRITY has no control over the information that third parties acquire via Embeds or what they do with it. This Privacy Statement does not apply to data gathered via Embeds. Before interacting with the Embed, it is recommended that you review the privacy policy of the third party hosting the Embed, which governs any information the Embed gathers.
INFORMATION TRANSFER TO THE UNITED STATES AND OTHER NATIONS
INTΞGRITY’s headquarters are located in the United States, and we have operations and service suppliers in other nations. Therefore, we and our service providers may transmit, store, or access your personal information in jurisdictions that may not provide a similar degree of data protection to your home jurisdiction. For instance, we transfer personal data to Amazon Web Services, one of our service providers that processes personal information on our behalf in numerous data centers throughout the world, including those indicated above. We shall take measures to guarantee that your personal information is adequately protected in the jurisdictions where it is processed.
YOUR SETTINGS
Account Specifics
You can access, modify, delete, and export your account information at any time by login into the Services and visiting the Settings page. Please be aware that if you delete your account, we may preserve certain information on you as needed by law or for our legitimate business purposes.
Cookies
The majority of web browsers accept cookies by default. You can often configure your browser to delete or refuse cookies if you wish. Please be aware that removing or rejecting cookies may impact the accessibility and performance of our services.
Communications
You may opt out of getting certain messages from us, such as digests, newsletters, and activity notifications, by following the instructions contained within those communications or by visiting the Settings page of your account. Even if you opt out, we may still send you emails regarding your account or our ongoing business relationships.
Mobile Push Notifications
We may send push notifications to your mobile device with your permission. You can cancel these messages at any time by modifying your mobile device's notification settings.
YOUR CALIFORNIA PRIVACY RIGHTS
The California Consumer Privacy Act, or "CCPA" (Cal. Civ. Code 1798.100 et seq. ), grants California residents some rights regarding their personal data. If you are a California resident, you are subject to this clause.
We have collected the following categories of personal information over the past year: identifiers, commercial information, internet or other electronic network activity information, and conclusions. Please refer to the section titled "Collection of Information" for specifics regarding the data points we gather and the sorts of sources from which we acquire them. We collect personal information for the business and marketing purposes outlined in the section on Use of Information. In the past 12 months, we have shared the following types of personal information to the following groups of recipients for business purposes:
Category of Personal Information: Identifiers
Categories of Recipients: Analytics Providers, Communication Providers, Custom Service Providers, Fraud Prevention and Security Providers, Infrastructure Providers, Marketing Providers, Payment Processors
Category of Personal Information: Commercial Information
Categories of Recipients: Analytics Providers, Infrastructure Providers, Payment Processors
Category of Personal Information: Internet or Other Electronic Network Activity Information
Categories of Recipients: Analytics Providers, Infrastructure Providers
Category of Personal Information: Inferences
Categories of Recipients: Analytics Providers, Infrastructure Providers
INTΞGRITY does not sell personally identifiable information.
You have the right, subject to certain limitations: (1) to request more information about the categories and specific pieces of personal information we collect, use, and disclose about you; (2) to request the deletion of your personal information; (3) to opt out of any future sales of your personal information; and (4) to not be discriminated against for exercising these rights. You may submit these requests by email to hello@int3grity.com. We shall not treat you differently if you exercise your rights under the CCPA.
If we receive your request from an authorized agent, we may request proof that you have granted the agent a valid power of attorney or that the agent otherwise possesses valid written authorization to submit requests on your behalf. This may involve requiring identity verification. Please contact us if you are an authorized agent wishing to make a request.
ADDITIONAL DISCLOSURES FOR INDIVIDUALS IN EUROPE
This section applies to you if you are based in the European Economic Area ("EEA"), the United Kingdom, or Switzerland and have specific rights and safeguards regarding the processing of your personal data under relevant law.
Legal Justification for Processing
We will process your personal information based on the following legal grounds:
To fulfill our obligations under our agreement with you (e.g., providing the products and services you requested).
When we have a legitimate interest in processing your personal information to operate our business or to safeguard our legitimate interests, we will do so (e.g., to provide, maintain, and improve our products and services, conduct data analytics, and communicate with you).
To meet our legal responsibilities (e.g., to maintain a record of your consents and track those who have opted out of non-administrative communications).
If we have your permission to do so (e.g., when you opt in to receive non-administrative communications from us). When consent is the legal basis for our processing of your personal information, you may at any time withdraw your consent.
Data Retention
We retain the personal information associated with your account so long as your account is active. If you close your account, your account information will be deleted within 14 days. We retain other personal data for as long as is required to fulfill the objectives for which it was obtained and for other legitimate business purposes, such as to meet our legal, regulatory, or other compliance responsibilities.
Data Access Requests
You have the right to request access to the personal data we hold on you and to get your data in a portable format, to request that your personal data be rectified or erased, and to object to or request that we restrict particular processing, subject to certain limitations. To assert your legal rights:
If you sign up for an INTΞGRITY account, you can request an export of your personal information at any time via the Settings website, or by visiting Settings and selecting Account from inside our app.
You can edit the information linked with your account on the Settings website, or by navigating to Settings and then Account in our app, and the Customize Your Interests page.
You may withdraw consent at any time by deleting your account via the Settings page, or by visiting Settings and then selecting Account within our app (except to the extent INTΞGRITY is prevented by law from deleting your information).
You may object to the use of your personal information at any time by contacting hello@int3grity.com.
Questions or Complaints
If we are unable to settle your concern over our processing of personal data, you have the right to file a complaint with the Data Protection Authority in your country. The links below provide access to the contact information for your Data Protection Authority.
For people in the EEA, please visit https://edpb.europa.eu/about-edpb/board/members en.
For persons in the United Kingdom, please visit https://ico.org.uk/global/contact-us.
For people in Switzerland: https://www.edoeb.admin.ch/edoeb/en/home/the-fdpic/contact.html
CONTACT US
Please contact us at hello@int3grity.com if you have any queries regarding this Privacy Statement.

Laura Sanders
3 years ago
Xenobots, tiny living machines, can duplicate themselves.
Strange and complex behavior of frog cell blobs
A xenobot “parent,” shaped like a hungry Pac-Man (shown in red false color), created an “offspring” xenobot (green sphere) by gathering loose frog cells in its opening.
Tiny “living machines” made of frog cells can make copies of themselves. This newly discovered renewal mechanism may help create self-renewing biological machines.
According to Kirstin Petersen, an electrical and computer engineer at Cornell University who studies groups of robots, “this is an extremely exciting breakthrough.” She says self-replicating robots are a big step toward human-free systems.
Researchers described the behavior of xenobots earlier this year (SN: 3/31/21). Small clumps of skin stem cells from frog embryos knitted themselves into small spheres and started moving. Cilia, or cellular extensions, powered the xenobots around their lab dishes.
The findings are published in the Proceedings of the National Academy of Sciences on Dec. 7. The xenobots can gather loose frog cells into spheres, which then form xenobots.
The researchers call this type of movement-induced reproduction kinematic self-replication. The study's coauthor, Douglas Blackiston of Tufts University in Medford, Massachusetts, and Harvard University, says this is typical. For example, sexual reproduction requires parental sperm and egg cells. Sometimes cells split or budded off from a parent.
“This is unique,” Blackiston says. These xenobots “find loose parts in the environment and cobble them together.” This second generation of xenobots can move like their parents, Blackiston says.
The researchers discovered that spheroid xenobots could only produce one more generation before dying out. The original xenobots' shape was predicted by an artificial intelligence program, allowing for four generations of replication.
A C shape, like an openmouthed Pac-Man, was predicted to be a more efficient progenitor. When improved xenobots were let loose in a dish, they began scooping up loose cells into their gaping “mouths,” forming more sphere-shaped bots (see image below). As many as 50 cells clumped together in the opening of a parent to form a mobile offspring. A xenobot is made up of 4,000–6,000 frog cells.
Petersen likes the Xenobots' small size. “The fact that they were able to do this at such a small scale just makes it even better,” she says. Miniature xenobots could sculpt tissues for implantation or deliver therapeutics inside the body.
Beyond the xenobots' potential jobs, the research advances an important science, says study coauthor and Tufts developmental biologist Michael Levin. The science of anticipating and controlling the outcomes of complex systems, he says.
“No one could have predicted this,” Levin says. “They regularly surprise us.” Researchers can use xenobots to test the unexpected. “This is about advancing the science of being less surprised,” Levin says.
